外研版八上Module_8_Accidents_Unit_1_While_the_lights_were_changing_to_red,_a_car_suddenly_appeared..pptVIP

when，while，as都可以引导时间状语从句，但用法区别非常大。 一、when可以和延续性动词连用，也可以和短暂性动词连用；而while和as只能和延续性动词连用。 e.g. They arrived while we were having dinner. = They arrived when we were having dinner. 我们吃饭的时候他们到了。 二、由when引导的时间状语从句，如果主句是过去进行时，从句应该用一般过去时，表示一个动作正在进行的时候另一个动作突然发生了，强调后一动作发生的突然性。 e.g. We were talking when the teacher came in. 我们正在讲话，老师（突然）进 来了。 三、当主句和从句的动作都是延续的或同时发生的，两句都用过去进行时的时候，多用while引导。 e.g. They were singing while were dancing. 他们在唱歌，我们在跳舞。 The boy __________ basketball yesterday. played They ____________ basketball at 4 p.m. yesterday. were playing They ____ a birthday party last night. had They ___________ a birthday party at nine last night. were having pale appear round corner hit glad risk attention side pay attention 注意；留心 in time 及时 并排地；肩并肩地 side by side 从……跌落 fall off accident driver happen mobile phone policeman road The driver was/was not going fast. The driver was/was not looking. The driver was/was not talking on his mobile phone. Who saw the accident? 2. Did the car stop just in time? Ms James. Yes, it did. 1. What was the boy doing when he was riding his bike? He was listening to music. 2. When did a car suddenly appear round the corner? While the lights were changing to red. 3. Did the boy fall off his bike? Yes, he did. When you are riding a bike, think about the risk of an accident! Pay ___________ and stop at the ___________. Don’t ______ too fast. Don’t ride ____________ with your friends. Don’t ______________! attention red lights ride side by side listen to music appear attention glad hit side Accidents do not happen very often, I’m (1) _____ to say. However, when you’re riding your bike, pay (2) _________ all the time, especially on the corner of the road and at traffic lights. Don’t ride side by (3) _____ with your friends. Some