Unit 3 Enviornmental protection【核心句式】-2021-2022学年高二英语下册链接教材精准变式练（人教版2019选择性必修第三册）

核心句式 Unit3 （解析版） 2021-2022学年高二英语下册链接教材精准变式练（人教版2019） ( 教材 核心词汇 知识链接 及典例解读 ) 1. 动词不定式的完成式 教材 P26》An expert who has studied polar bears for many years said that from the position of its dead body，the bear appeared to have starved and died.一位多年研究北极熊的专家说，从北极熊尸体所处的位置来看，它似乎是饿死的。 句式剖析 本句的结构分析如下∶ An expert who has....many years said 主语 定语从句 谓语 （动词不定式的完成式） that...body, the bear appeared(to have starved and died). 宾语从句 考点提炼 动词不定式的完成式 该结构的具体用法为∶ （1） 动词不定式的完成式所表示的动作发生在谓语动词所表示的动作之前。 （2）动词不定式的完成式常用在 appear，seem，think，consider，believe等表示看法与想法的动词后。 （3）该结构也常用以 it作形式主语的句型代替，即It appears/seems/is thought/is believed/...that...have/ has done..。 相当于It appeared that she had know She appeared to have known the result of the competition as she showed no surprise at all when I told her that she had won first prize.她似乎已经知道了比赛结果，因为当我告诉她她得了一等奖时，她一点也不惊讶。 相当于St is believed that up t 12 survivors have been rescued Up to 12 survivors are believed to have been rescued from the fire so far.到目前为止，据信有多达12名幸存者在火灾中获救。 相当于It seems that the Clarks have left for holiday The Clarks seem to have left for holiday. Their house has been empty for days.克拉克-家似乎已去度假了。他们的房子已经空了好几天了。 归纳拓展相关知识积累∶ (1) 动词不定式的完成式常同 expect，hope等连用，表示预计将来完成的动作。 I expect to have read this book by Friday.我预计星期五前就读完这本书。 I hope to have finished the work by the end of the year.我希望年底前就完成这项工作。 （2） 动词不定式的完成式也可与mean，think，intend，promise 等表示意图、打算、计划等的动词过去式连用，表示想做但未曾实现的愿望或计划等。 I intended to have come to see you.我本打算来看你的。（但没能来） I meant to have called you last night.我本打算昨晚给你打电话的。（但没打电话） 1.语法填空 ①（浙江高考语法填空改编）While regularly eating out seems ___________(become)common for many young people in recent years,it's not without a cost . ②He is thought_____________ (act) foolishly.Now he has no one but himself to blame for losing the job. 2.情境写作（to have done） ①（江苏南京师大附中期中）结交了这么多新朋友，我感到非常幸运。 __________________________________________________________ ②发动机启动不了了，它好像出间题了。 __________________________________________________________（it作形式