Unit 1 Science and Scientists Reading and Thinking 导学案-2026-2027学年高中英语人教版选择性必修第二册

PEP (2019) Selective Compulsory Book 2 · Unit 1 Science and Scientists Reading and Thinking · The Detective Who Beat "King Cholera" Grade 11 English · Reading class · 1 period (45 min) Class: ________ Name: ________ Group: ______ [Your Assignment] You are a junior investigator at the city public health unit. Your first case: the 1854 Broad Street cholera outbreak in London, cracked by a doctor named John Snow — the father of modern epidemiology. Work through the case file. By the end you will write a short brief connecting his method to how our city fights disease today. Learning Goals (tick after class) 1. I can retell Snow's investigation in order: problem → question → method → data → analysis → evidence → conclusion. □ done □ need more work 2. I can point to the exact lines that show how Snow proved the pump water was the killer. □ done □ need more work 3. I can compare Snow's 1854 map with Wuhan's 2020 contact tracing and say what they share. □ done □ need more work 4. I can write an 80–100-word public health brief about Snow for a school newsletter. □ done □ need more work ★ 本课重点：Snow怎么通过地图对比锁定Broad Street水泵是传染源；那两个额外死亡病例为什么是关键证据。 ☆ 本课难点：从Snow的个案上升到科学方法的共性——把他的方法和武汉2020流调对应起来。 Part 1 Before You Read Task 1 Wuhan Water, Then and Now The water from your tap at home comes from the Yangtze and Han rivers. In 1854 London, people drank water straight from the Thames. Cholera was killing hundreds in days — severe diarrhoea, dehydration, then death. Nobody knew why. Talk with a partner: 1. If people on one street were getting sick but the next street was fine, what would you check first? Circle TWO: □ the air they breathe □ the water they drink □ the food they eat □ the houses they live in (Acceptable: water and food. Teacher confirms water leads to the pump.) 2. Think back to early 2020 in Wuhan. Doctors and disease-control workers were mapping every case, every close contact, every possible source. That is the same detective instinct Snow had 166 years earlier. What were they both trying to do? My answer: ________________________________________________________________ Task 2 Order the Detective's Steps A detective follows a sequence. Number these steps 1–7 in the order you think Snow used them: ( ) analyse the results ( ) ask a question ( ) draw a conclusion ( ) collect data ( ) find a problem ( ) find supporting evidence ( ) think of a method Part 2 While You Read Task 3 The Crime Scene (Paragraph 1) Skim Paragraph 1 and fill in the case file: Details from the text What is cholera? When and where? What did it do? Who is John Snow? Teacher tip: Don't just write "a disease" — what are the symptoms? And Snow wasn't some unknown doctor — find out who he was. Task 4 Two Theories on Trial (Paragraph 2) Two ideas about how cholera spread. Read Paragraph 2 and fill in the chart: Theory 1 Theory 2 What caused cholera? Which theory did Snow believe? How bad was the 1854 outbreak? Task 5 The Map That Cracked the Case (Paragraph 3) [本课重点] This is the heart of the story. Snow didn't guess — he mapped. Read Paragraph 3 and complete the chart. Pay special attention to step (4) — the contrast between deaths near the pump and houses with zero deaths. Step What Snow did / what he found (key words from text) (1) Find a problem (2) Think of a method He decided to draw a map to study where people died. (3) Collect data (4) Analyse the results (5) Find supporting evidence Two extra deaths: people who lived far away but had the pump water delivered to their homes. ★ Why are those two extra deaths the key? They lived far from Broad Street, yet they died — because they had the pump water delivered. Without them, Snow's conclusion was only a guess. With them, it was proof. Underline them in the text. Task 6 The Verdict (Paragraphs 4 & 5) Answer the closing questions: 1. What was the truth? What was in the water? ________________________________________________________________ 2. What did Snow actually do to stop the outbreak? ________________________________________________________________ 3. What was Snow's lasting contribution? ________________________________________________________________ Part 3 After You Read Task 7 Wuhan Connection — Then and Now [本课难点] Group work (4 students). Compare Snow in 1854 London with Wuhan disease-control workers in 2020. Fill in the Wuhan column. Don't just say "both fought disease" — tell me the METHOD, not the details. Step John Snow, 1854 London Wuhan disease-control, 2020 Find a problem Cholera spreading on Broad Street Collect data Mapped deaths on a street map Analyse results Deaths clustered near the water pump Evidence → Conclusion Pump water carried cholera germs; remove the handle Teacher tip: If your group says "both wore masks" or "both had lockdowns", you're on the wrong track. Think: what did they both DO to find the source and cut it off? Task 8 What Made Snow Different? Go back to the text. Pick TWO qualities of Snow and copy the exact line that shows it. "He was smart" doesn't count without evidence. Quality Line from the text (copy it) What it tells us e.g. determined "John never lost his desire to defeat cholera." He didn't give up when no one knew the cause. Summary Cholera was "King" of London until one doctor refused to guess. He mapped, he checked, he found the water pump — and he changed how science fights disease. In Wuhan today, we still use the same detective mind. Complete: Snow defeated King Cholera by ____________, and his method still works in Wuhan because ____________. Homework Required: You work at Wuhan CDC. Write an 80–100-word brief for a school health newsletter: introduce John Snow, explain his method in 3 steps, and end with one sentence about why his work matters to Wuhan today. Start: In 1854, a London doctor named John Snow faced a deadly disease called cholera. First, he… Then he… Finally, he… Today, his method still helps Wuhan because… Optional (choose one): ① Write a short dialogue (6–8 lines) between John Snow and a Wuhan CDC worker today. ② Write a letter from Snow to a modern scientist. ③ Design a poster: "Three Rules for a Young Detective-Scientist." Self-check after writing: □ I explained Snow's method in 3 clear steps □ I wrote one sentence connecting Snow to Wuhan today □ My brief is 80–100 words Answer Key Task 2 find a problem (1) → ask a question (2) → think of a method (3) → collect data (4) → analyse the results (5) → find supporting evidence (6) → draw a conclusion (7). Task 3 Cholera: causes severe diarrhoea, dehydration, and even death. When and where: the outbreak Snow investigated hit London (Broad Street) in 1854; Paragraph 1 also notes an earlier early-19th-century outbreak across Europe in which millions died. Snow: a famous London doctor who attended Queen Victoria when she gave birth; he never lost his desire to destroy cholera once and for all. Task 4 Theory 1: bad air. Theory 2: germs in food or water. Snow believed Theory 2. More than 500 people died in 10 days on two particular streets. Task 5 ★ 重点 (1) Cholera outbreak on two particular streets; Snow wanted to find out why. (3) He marked house numbers on the map — deaths clustered near the Broad Street pump. (4) Most deaths were near the pump; some households had no deaths at all — this contrast is the key. Task 6 1. The pump water was polluted — it carried cholera germs. 2. He had the pump handle removed so it couldn't be used. 3. He is the father of modern epidemiology — he transformed the way scientists use maps and statistics. Task 7 ☆ 难点 Wuhan column (acceptable answers): problem = unknown disease spreading; collect data = tracking every case and close contact; analyse = finding clusters and common exposure; evidence/conclusion = identifying the source and cutting off transmission chains. Task 8 e.g. determined ("never lost his desire"); methodical (he mapped instead of guessing); brave/caring (he faced a deadly disease to protect ordinary people). Any quality backed by a quoted line works. Summary: Snow defeated cholera by mapping and tracing the water supply; his method still works in Wuhan because modern disease detection follows the same find–collect–analyse–evidence–conclusion chain. 学科网（北京）股份有限公司 $