补充练习：

1.　　　 When he arrived at the bus stop, the bus ________ for 20 minutes.

A. has left　　 B. had left　 C. has been away　　 D. had been away

非延续性动词在肯定句中与表示时间点的状语连用，如：two years ago; at 5 o'clock;

例:He died 5 years ago.

　　 否定的终止性动词可以与表示时间段的时间状语连用。例:I haven't left here for 3 years. I haven't heard from him for 3 weeks.

　　 表示时间段的短语有:for+一段时间,for 2 years; since从句,since he came here; since+时间点名词,since last year, since 5 days ago; how long; for a long time等。

　　 例:He has lived here for 6 years.　 You can keep the book for 5 days. I stayed there for 2 weeks last year.　 How long did you stay there last year?

1.有很多游客，他们给猴子喂食，和老虎玩耍。

2.动物和人很友好，我们应该善待动物。

3.保护环境非常重要，动物园内不要随地扔垃圾。

4.知道了野生动物保护的重要性。因为保护动物就是保护我们自己。

8. 她只想着自己，从不关心他人。

She only________ of herself and doesn’t_______ _______ others.

7. 人们通过向希望工程捐助帮助贫困地区的学校和学生。

People help schools and students in poor _______ by_______ ______ to Project Hope.

6. 我们希望你不要轻视这种工作。

We hope you won’t ________ down _______ this kind of work.

5. 他没有足够的钱进行医疗诊治。

He doesn’t have ______ money_______ ________ treatment.

4. 请提供给我们一些食品。

Please _______ us _________ some food.

3. 十年来我们学校发生了巨大的变化。

Great changes _______ ______ _______ in our school since ten years ago.