Unit 3 Sea Exploration-Learning About Language 教案-2025-2026学年高中英语人教版选择性必修第四册

Unit 3 Sea Exploration-Learning About Language 内容导航 This lesson, centered on the theme of sea exploration, focuses on integrating vocabulary related to marine exploration, maritime trade and cultural exchange with the grammatical structure of the infinitive. It guides students to discover, summarize and apply the infinitive’s functions (as subject, predicate, object, attribute, adverbial and object complement) through context and practical exercises, helping them consolidate language knowledge, improve language application ability and lay a solid foundation for subsequent listening, speaking, reading and writing tasks related to the unit theme. It also connects with the unit’s core context of "sea exploration" to realize the integration of language learning and theme development. 教学目标和重难点 1. 教学目标 Language Competence: Master core vocabulary and phrases related to sea exploration, and proficiently use the infinitive in different sentence structures to express ideas accurately. Cultural Awareness: Understand the historical and contemporary significance of sea exploration, recognize China’s contributions to maritime civilization and enhance cultural confidence. Thinking Quality: Develop logical thinking through summarizing the infinitive’s usages and critical thinking through discussing language application scenarios. Learning Ability: Master effective language learning strategies such as context-based learning and cooperative inquiry, and form the awareness of autonomous learning and continuous improvement in language practice. 2. 教学重难点 Key Points: Master core vocabulary and phrases related to sea exploration (e.g., voyage, exploration, negotiate trade deals, strengthen the bonds) and the basic structure and six syntactic functions of the infinitive. Be able to correctly identify and use the infinitive in simple sentences. Difficult Points: Distinguish the differences between the infinitive’s different functions (especially as attribute, adverbial and object complement) in specific contexts; flexibly use the infinitive to express intentions, purposes and states in practical communication; and accurately apply the infinitive in combination with the theme of sea exploration to avoid common grammatical mistakes. 教学过程 Step 1: Lead-in (Warm-up and Activation) Activity 1: Theme-related Video and Question Interaction The teacher plays a 3-minute short video about sea exploration, which includes scenes of ancient maritime Silk Road trade, Zheng He’s voyages to the Western Seas, modern deep-sea exploration with advanced technology and marine ecological protection. After playing the video, the teacher asks students the following questions in English: "What scenes did you see in the video? What do you think is the significance of sea exploration? Can you use some English words to describe the video content?" Students are invited to answer freely. The teacher writes down the words and phrases mentioned by students on the blackboard, such as "sea exploration", "voyage", "ship", "trade", "cooperation", "deep sea", "marine life" and "protection". Then the teacher supplements core vocabulary related to the unit, such as "negotiate trade deals", "strengthen the bonds", "marine ecosystem", "deep-sea exploration" and "cultural exchange", and reads them aloud with students to help students familiarize themselves with the pronunciation and meaning of the words. Design Intention: The short video with vivid images and rich content can quickly attract students’ attention, arouse their interest in the theme of sea exploration and activate their existing knowledge reserve related to the theme. By asking questions and encouraging students to express themselves freely, it creates a relaxed English communication atmosphere, lays a foundation for the subsequent vocabulary and grammar learning, and realizes the connection between the lesson and the unit theme. At the same time, supplementing core vocabulary in advance helps students reduce language barriers in the subsequent learning process. Activity 2: Sentence Recognition and Doubt Raising The teacher presents 6 sentences on the screen, all selected from the unit text and containing the infinitive structure, which are closely related to the theme of sea exploration: 1. To complete the great map of the world was a strong passion for the people of early civilisations. 2. Marco Polo’s tales inspired European explorers to search for sea routes from west to east. 3. Merchants from China and many other places met to negotiate trade deals. 4. These fleets were a sight to behold and were in a league of their own at that time. 5. The aim of this initiative is to encourage cooperation and trade across the historic Silk Road areas. 6. The need to trade and the desire to enhance relationships will drive China to reach out across the sea. The teacher asks students to read the sentences aloud in groups of two, observe carefully and discuss: "What is the common structure in these sentences? What role does this structure play in each sentence?" After 3 minutes of group discussion, the teacher invites representatives of each group to share their findings. The teacher does not give the answer directly, but guides students to find that all sentences contain the structure "to + verb原形" and that this structure has different functions in different sentences, thus leading to the core content of this lesson——the infinitive. Design Intention: By presenting sentences closely related to the unit theme, students can perceive the infinitive in a familiar context, avoiding the boredom of pure grammar explanation. Group discussion encourages students to participate actively, cultivate their cooperative learning ability and observation ability. Guiding students to discover the characteristics of the infinitive by themselves conforms to the student-centered teaching concept, helps students deepen their understanding of the infinitive and lays a foundation for the subsequent detailed explanation of its functions. Step 2: Vocabulary Learning (Consolidation and Application) Activity 1: Vocabulary Classification and Explanation The teacher sorts out the core vocabulary of this lesson according to the theme of sea exploration, divides them into three categories and explains them in detail with specific examples and contexts: 1. Vocabulary related to sea exploration: exploration (n. 探索), voyage (n. 航行), set sail (启航), deep-sea exploration (深海探索), marine (adj. 海洋的), oceanography (n. 海洋学), hydrothermal vent (热液喷口). For example, the teacher explains "voyage" by saying: "Zheng He made seven voyages to the Western Seas in the Ming Dynasty, which promoted cultural and trade exchanges between China and other countries." For "marine ecosystem", the teacher says: "We should protect the marine ecosystem to avoid the extinction of marine life." 2. Vocabulary related to trade and cooperation: negotiate (v. 谈判), trade deals (贸易协议), cooperation (n. 合作), strengthen (v. 加强), bonds (n. 联系), invest (v. 投资), for the benefit of (为了……的利益). The teacher combines the unit text to explain: "Merchants from all over the world met to negotiate trade deals, which strengthened the bonds between different countries." 3. Common verbs followed by the infinitive: inspire (sb. to do sth.), encourage (sb. to do sth.), decide (to do sth.), hope (to do sth.), want (to do sth.), manage (to do sth.), pretend (to do sth.). The teacher gives example sentences for each verb: "His story inspired us to work harder. She decided to participate in the sea exploration project." After the explanation, the teacher leads students to read the words and example sentences aloud, pays attention to correcting students’ pronunciation and intonation, and asks students to make simple sentences with each word or phrase in combination with the theme of sea exploration. Design Intention: Classifying vocabulary according to the theme helps students establish a systematic vocabulary network and connect vocabulary learning with the unit theme closely. Explaining vocabulary with specific examples and contexts makes it easier for students to understand and remember the meaning and usage of words. Asking students to make sentences by themselves can test their mastery of vocabulary and lay a foundation for the subsequent grammar learning and language application. Activity 2: Vocabulary Practice (Fill in the Blanks and Translation) The teacher presents the following fill-in-the-blank exercises on the screen, requiring students to complete them with the core vocabulary learned just now. After students finish, the teacher checks the answers and explains the key points: 1. Many countries are carrying out ________ (深海探索) to discover the secrets of the ocean. 2. The two countries signed a contract to ________ (加强) their cooperation in marine research. 3. The merchants spent three days ________ (谈判) the trade deals. 4. Zheng He’s ________ (航行) contributed greatly to the cultural exchange between China and foreign countries. 5. We should protect the ________ (海洋生态系统) to ensure the sustainable development of the ocean. Then, the teacher arranges translation exercises, asking students to translate the following Chinese sentences into English, using the learned vocabulary and the infinitive structure: 1. 他的梦想是成为一名海洋科学家，探索海洋的奥秘。(dream, marine scientist, explore) 2. 政府鼓励年轻人参与海洋保护活动。(encourage, participate in, marine protection) 3. 他们决定启航去进行一次为期一个月的海上航行。(decide, set sail, voyage) Students complete the exercises independently, and then the teacher invites several students to present their answers on the blackboard. The teacher corrects the mistakes, especially the usage of vocabulary and the infinitive, and emphasizes the key points and difficult points. Design Intention: Fill-in-the-blank exercises help students consolidate the spelling and meaning of vocabulary, while translation exercises help students connect Chinese and English, improve their language application ability and combine vocabulary learning with grammar learning. Independent completion and public presentation can test students’ mastery of knowledge, help the teacher grasp students’ learning situation in time, and provide targeted guidance for the subsequent teaching. Step 3: Grammar Learning (Discovery, Summary and Practice) Activity 1: Exploring the Functions of the Infinitive The teacher reviews the 6 sentences presented in the lead-in part, and guides students to analyze the function of the infinitive in each sentence one by one, combining with the context of sea exploration: 1. To complete the great map of the world was a strong passion for the people of early civilisations. (The infinitive phrase "To complete the great map of the world" is used as the subject, indicating a specific action or purpose.) The teacher explains: "When the infinitive is used as the subject, it usually expresses a specific action or purpose. We can also rewrite the sentence as ‘It was a strong passion for the people of early civilisations to complete the great map of the world’, where ‘it’ is the formal subject and the infinitive phrase is the real subject." Then the teacher gives another example related to sea exploration: "It is important for us to protect the marine environment." 2. Marco Polo’s tales inspired European explorers to search for sea routes from west to east. (The infinitive "to search for..." is used as the object complement, explaining the action of the object "European explorers".) The teacher emphasizes: "Some verbs, such as inspire, encourage, ask, tell, want, etc., can be followed by ‘sb. + to do sth.’, where the infinitive is the object complement." Then the teacher asks students to make a sentence with "inspire sb. to do sth." combined with sea exploration. 3. Merchants from China and many other places met to negotiate trade deals. (The infinitive "to negotiate..." is used as the adverbial of purpose, indicating the purpose of the action "met".) The teacher explains: "When the infinitive is used as the adverbial of purpose, it usually means ‘in order to do sth.’. We can add ‘in order’ or ‘so as’ before the infinitive, such as ‘Merchants met in order to negotiate trade deals.’" Then the teacher guides students to find other sentences in the unit text that use the infinitive as the adverbial of purpose. 4. These fleets were a sight to behold and were in a league of their own at that time. (The infinitive "to behold" is used as the attribute, modifying the noun "a sight".) The teacher explains: "When the infinitive is used as the attribute, it is usually placed after the modified noun, indicating the action related to the noun. For example, ‘a chance to go to sea’ (a chance to go to sea), ‘a plan to explore the deep sea’ (a plan to explore the deep sea)." Then the teacher asks students to make phrases with the infinitive as the attribute, combined with the theme of sea exploration. 5. The aim of this initiative is to encourage cooperation and trade across the historic Silk Road areas. (The infinitive phrase "to encourage..." is used as the predicative, explaining the content of the subject "the aim".) The teacher says: "When the infinitive is used as the predicative, it is usually placed after the linking verb (such as be, seem, appear) to explain the content or purpose of the subject. For example, ‘Our goal is to protect the ocean.’" 6. The need to trade and the desire to enhance relationships will drive China to reach out across the sea. (The infinitive phrases "to trade" and "to enhance..." are used as the attributes, modifying "the need" and "the desire" respectively; the infinitive "to reach out..." is used as the object complement.) After analyzing each sentence, the teacher summarizes the six syntactic functions of the infinitive on the blackboard: subject, predicative, object, attribute, adverbial of purpose and object complement, and briefly combs the key points of each function, combining with examples related to sea exploration. Design Intention: Guiding students to analyze the function of the infinitive in specific sentences helps them understand the usage of the infinitive in context, avoiding the abstractness of pure grammar explanation. Combining with the unit theme of sea exploration makes grammar learning more targeted and interesting. Summarizing the functions of the infinitive helps students form a systematic understanding of the infinitive and lay a foundation for subsequent practice. Activity 2: Distinguishing Similar Functions The teacher presents several groups of confusing sentences on the screen, requiring students to distinguish the function of the infinitive in each sentence and explain the reasons. The sentences are closely related to the theme of sea exploration: Group 1: a. To explore the deep sea is very challenging. (Infinitive as subject) b. His dream is to explore the deep sea. (Infinitive as predicative) Group 2: a. We need a ship to sail across the ocean. (Infinitive as attribute) b. We set sail to cross the ocean. (Infinitive as adverbial of purpose) Group 3: a. He wants to join the sea exploration team. (Infinitive as object) b. He asked me to join the sea exploration team. (Infinitive as object complement) Students discuss in groups of four, and then each group selects a representative to explain their answers. The teacher comments and supplements, emphasizing the key points of distinguishing similar functions: when the infinitive is used as the subject, it is the core of the sentence, representing an action; when it is used as the predicative, it explains the content of the subject; when it is used as the attribute, it modifies the preceding noun; when it is used as the adverbial of purpose, it indicates the purpose of the preceding action; when it is used as the object, it follows the verb directly; when it is used as the object complement, it follows the object and explains the action of the object. Design Intention: Confusing sentence groups can help students focus on the differences between similar functions of the infinitive, deepen their understanding of the infinitive’s functions and avoid mistakes in use. Group discussion encourages students to exchange ideas, learn from each other and improve their logical thinking ability and language analysis ability. The teacher’s comment and supplement can help students clarify their misunderstandings and grasp the key points of distinction. Activity 3: Grammar Practice (Multiple Choice and Sentence Rewriting) First, the teacher arranges multiple-choice exercises to test students’ mastery of the infinitive’s functions. The questions are closely related to the theme of sea exploration, and the options are designed according to common mistakes: 1. ______ the ocean’s mysteries is the dream of many marine scientists. ( ) A. Explore B. To explore C. Exploring D. Explored 2. The government encourages people ______ more attention to marine protection. ( ) A. pay B. paying C. to pay D. paid 3. We have a plan ______ a voyage around the world next year. ( ) A. make B. to make C. making D. made 4. The sailors set sail early ______ they could reach the destination on time. ( ) A. to B. in order to C. so that D. in order that Students complete the exercises independently, and then the teacher checks the answers, explains the reasons for each option and emphasizes the common mistakes, such as confusing the infinitive with the gerund as the subject, forgetting "to" after verbs such as encourage and want, and confusing the infinitive as attribute with adverbial of purpose. Then, the teacher arranges sentence rewriting exercises, requiring students to rewrite the sentences according to the requirements, using the infinitive structure: 1. It is important for us to protect marine life. (Rewrite the sentence, putting the infinitive phrase as the subject) 2. He decided that he would participate in the deep-sea exploration project. (Rewrite the sentence with the infinitive as the object) 3. The merchants met because they wanted to negotiate trade deals. (Rewrite the sentence with the infinitive as the adverbial of purpose) 4. The book tells us some stories about sea exploration. (Rewrite the sentence, using the infinitive as the attribute to modify "stories") After students finish rewriting, the teacher invites several students to present their answers, corrects the mistakes and summarizes the key points of rewriting, helping students flexibly use the infinitive in different sentence structures. Design Intention: Multiple-choice exercises can quickly test students’ mastery of the infinitive’s functions and common mistakes, helping the teacher grasp students’ learning situation in time. Sentence rewriting exercises can help students flexibly apply the infinitive’s functions, improve their ability to adjust sentence structures and lay a foundation for subsequent comprehensive language application. Independent completion and public presentation can enhance students’ sense of participation and confidence in learning grammar. Step 4: Comprehensive Application (Integration of Vocabulary and Grammar) Activity 1: Group Discussion and Short Speech The teacher divides students into groups of 5, and assigns the discussion topic: "What do you think are the advantages and challenges of modern sea exploration? What should we do to promote the sustainable development of sea exploration?" The teacher requires students to use the core vocabulary and the infinitive structure learned in this lesson to express their views, and each group appoints a recorder to record the key points of the discussion. During the discussion, the teacher walks around the classroom, guides students who have difficulties in expression, reminds students to use the learned vocabulary and grammar, and ensures that every student participates in the discussion. After 10 minutes of discussion, each group selects a representative to give a 2-3 minute short speech, introducing the group’s views. The teacher listens carefully, records the advantages and disadvantages of students’ expression, and comments after all groups finish speaking, focusing on affirming students’ correct use of vocabulary and grammar, and putting forward suggestions for improvement. Design Intention: Group discussion and short speech integrate vocabulary and grammar learning, allowing students to apply the learned knowledge in practical communication, improving their oral expression ability and cooperative learning ability. The discussion topic is closely related to the unit theme and social reality, which can arouse students’ thinking, cultivate their critical thinking and sense of social responsibility. The teacher’s guidance and comment can help students find their own problems and improve their language application ability. Activity 2: Short Passage Writing The teacher asks students to write a short passage of 80-100 words with the title "My View on Sea Exploration", requiring students to use at least 5 core vocabulary words learned in this lesson and at least 3 sentences with the infinitive structure. The teacher provides a writing outline for students to refer to: 1. The significance of sea exploration (using the infinitive as subject or predicative); 2. The advantages or challenges of sea exploration (using the infinitive as adverbial of purpose or attribute); 3. Our responsibility (using the infinitive as object or object complement). Students write independently, and the teacher walks around the classroom to provide guidance for students who have difficulties in writing, such as how to use the infinitive correctly, how to organize the structure of the passage and how to use vocabulary appropriately. After students finish writing, the teacher collects some students’ works, reads them aloud in class, comments on them, affirms the advantages and points out the problems that need to be improved, such as grammar mistakes, inappropriate vocabulary use and unclear logic. Then students exchange their works in pairs, correct each other’s mistakes and put forward suggestions for improvement. Design Intention: Short passage writing is an important way to test students’ comprehensive language application ability, integrating vocabulary, grammar, writing skills and theme expression. Providing a writing outline helps students clarify the writing ideas and avoid disorganized writing. Independent writing, teacher guidance, peer evaluation and teacher comment form a complete writing teaching process, which helps students improve their writing ability, consolidate the learned vocabulary and grammar, and realize the integration of language learning and theme exploration. Step 5: Summary and Homework Activity 1: Lesson Summary The teacher invites students to summarize the key content of this lesson, including core vocabulary, the six functions of the infinitive and their usage points. Then the teacher supplements and combs, emphasizing that this lesson focuses on the integration of vocabulary and grammar related to sea exploration, and the infinitive is an important grammatical structure to express intentions, purposes and states, which is very useful in practical communication related to sea exploration. The teacher also reminds students to pay attention to the differences between the infinitive’s different functions and avoid common mistakes. Design Intention: Letting students summarize the lesson by themselves helps them sort out the knowledge learned, deepen their understanding and memory, and improve their ability to summarize and sort out knowledge. The teacher’s supplement and combing can help students form a systematic knowledge framework and clarify the key points and difficult points of the lesson. Activity 2: Homework Arrangement 1. Basic Homework: Review the core vocabulary and the infinitive’s functions learned in this lesson, copy the core vocabulary and example sentences twice, and complete 10 grammar exercises (focusing on the infinitive’s functions) provided by the teacher. 2. Improved Homework: Revise the short passage written in class according to the teacher’s and peers’ suggestions, and add 2 more sentences with the infinitive structure. 3. Extended Homework: Collect 5 English news sentences about sea exploration from the Internet or English newspapers, identify the function of the infinitive in each sentence, and bring them to class to share in the next lesson. Design Intention: The homework is designed in three levels, which conforms to the principle of differentiated teaching, meeting the needs of students with different learning levels. Basic homework helps students consolidate the knowledge learned in class; improved homework helps students improve their writing ability; extended homework connects classroom learning with extracurricular learning, broadens students’ horizons, increases their exposure to English, and further consolidates the usage of the infinitive. Step 6: Teaching Evaluation and Reflection (Teacher’s Internal Evaluation) During the whole teaching process, the teacher conducts formative evaluation on students’ performance, including their participation in warm-up activities, group discussions, vocabulary and grammar exercises, short speeches and short passage writing. The evaluation focuses on students’ mastery of vocabulary and grammar, their ability to apply language, their participation in activities and their cooperative learning ability. For students who perform well, the teacher gives timely praise and encouragement; for students who have difficulties, the teacher provides targeted guidance and help. After the lesson, the teacher will reflect on the teaching process: whether the teaching links are reasonable, whether the teaching activities are in line with students’ learning characteristics, whether the key points and difficult points are effectively broken through, whether students’ core literacy is effectively cultivated, and whether there are problems in the teaching process that need to be improved. According to the reflection, the teacher will adjust the teaching plan and improve the teaching effect of the next lesson. Design Intention: Formative evaluation runs through the whole teaching process, which helps the teacher grasp students’ learning situation in time, adjust the teaching progress and methods, and ensure the teaching effect. Teaching reflection helps the teacher summarize experience, find problems, improve teaching level continuously, and better realize the teaching goal of cultivating students’ core literacy. 1 / 1 学科网（北京）股份有限公司 学科网（北京）股份有限公司 学科网（北京）股份有限公司 $