howlifebeganontheearth语言点（仅供参考）.ppt

All this leads to the smog. The smog makes it __________(hard)for people _________ __ (breath). It prevents us from ______ out and______ activities. ___________the problem can be solved ______________(depend on) ___________the local government takes measures in time. I really hope that the air in my hometown can be fresh again and the smog won’t exist any more. hard to breathe going taking Whether depends on whether Show time Homework 1.Oral work: Review the language points. 2. Written work: Finish the exercise of Period Two in your workbook. Thank you 返回 返回 返回 返回 返回 返回 返回 How Life Began on the EarthLanguage study Unit 4 Why did many species(物种)like the dinosaurs die out? Air pollution ：smog smog = smoke + fog Movie about the smog lay-laid-laid-laying ① lay eggs 下蛋 lay 放, 把..放在..; 产卵 原句再现1: They laid eggs too and existed on the earth for more than 140 million years. Farmers lay straws(秸秆)in the fields. eg. The hen laid seven eggs. Language study lie, lie , lay 的区别如下: Tips: lay (laid; laid; laying) 放置;产卵 lie (lay; lain; lying) 躺;位于 lie (lied; lied; lying) 说谎 顺口溜: 规则的“说谎” （直接-d） 不规则的“躺” (完全不一致) 躺完就“下蛋” （lay） 下蛋不规则 Tom who____ on the grass ______to me that the hen had ____two eggs. lay lied laid ② exist vi. 存在；生存 Without air, we can’t exist even for one minute. 没有空气，我们甚至连一分钟都生存不了。 (1)There exist ... 存在……；有…… (2)existence n. 存在；生活 come into existence= come into being产生；开始存在 Language study 1．①Many problems are existing on your paper（改错）. ② Dinosaurs once were existed on the earth （改错）　 There existed dinosaurs on the earth a long time ago. 2．翻译句子 很久以前地球上存在着恐龙(dinosaur)。 Exercise There exist some factories in my hometown. 我家乡有些工厂(factory)。 exist ________ ________ existed What many scientists believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids