UNIT 4 Section Ⅱ Using language-【高考领航】2023-2024学年高中英语选择性必修第二册同步核心辅导与测评（外研版）

Section Ⅱ　Using language it作形式主语 观察下面教材中的句子并体会它们的语法特征 1．But it is vital not to take any chances. 2．When I saw the tragic scenes on the news，I felt it was my duty as a doctor to go there and offer my help. 3．It is important to remember that Ebola doesn't respect national boundaries. 4．It is so inspiring to have colleagues like Wilton，Maisy and Alfonso，not to mention all the others I have worked with. 5．In a world still facing so many problems，it is absolutely essential for us all to collaborate to create a global community with a shared future of peace and prosperity. 【语法感悟】 1．以上句子均为it作形式主语的句子。 2．以上句子真正的主语是动词不定式。 当动词不定式(短语)、动词-ing(短语)或者从句作句子的主语时，通常用it(不能用that、this等词)来作形式主语代替它们，而将真正的主语放在后面，以保持句子结构的平衡。此时it只起先行引导作用，本身无词义。 知识点1　it代替不定式(短语)作形式主语 it代替不定式(短语)作形式主语的常见句型： (1)It＋be＋形容词＋(for/of sb.) to do sth. (2)It＋be＋名词＋to do sth. (3)It takes (sb.) some time to do sth. (4)It's up to sb.to do sth. ◆(2021·全国甲卷)It is possible to walk or bike the entire 14 kilometers. 步行或骑自行车完成全程14公里是可能的。 ◆It is good manners for students to greet to their teachers. 学生向老师打招呼是礼貌的行为。 ◆It took us three hours to get there by bus. 乘公交车去那里要花费我们三个小时。 ◆It's up to us to help those in need. 帮助那些有困难的人是我们的职责。 [温馨提示]　在It＋be＋形容词＋for sb./of sb. ＋to do句型中。如果形容词描述不定式所表示动作的特征，介词用for；如果形容词描述的是人的品质、性格，介词用of。 ◆It is very important for us to learn how to deal with stress. 学会如何应对压力对我们来说很重要。 ◆It was really very kind of you to give me a lift home. 你让我搭便车回家，真是太好了。 [即时演练1]　单句语法填空 (1)(2021·天津卷)It was important for me to learn that you don't have to always get everything right the first time and that good things come with continual effort. (2)(2021·天津卷)Currently，about 35，000 works are being displayed in over 300 rooms in the Louvre，and it would take a lifetime_to_see (see)everything. (3)It is traditional to_bring(bring) a gift to a housewarming party. (4)It's generous of the little girl to_share (share) them with the others though she loves her toys so much. 知识点2　it代替动词-ing(短语)作形式主语 it代替动词-ing(短语)作形式主语的常见句型： It's no use/no