1.You needn't__have__written(write)such a long essay.The teacher only asked for 300 words，and you have written 600.

2.Mary can't__have__stolen (steal)your money.She has gone home.

3.There is nowhere to find them.Where can they have__gone(go)?

4.She didn't get there in time.She may__have__missed(miss)the bus.

5.Though you were busy，you could__have__helped(help)him.

6.The flowers have died.I should__have__watered (water)them often.

7.The light in his room is still on，so he can't__have__gone(go)out.

8.They could__have__finished(finish)the work yesterday，but it was raining hard.

9.If he had worked hard，he would__have__passed(pass)the College Entrance Examination.

10.I didn't hear the phone.I must__have__been__asleep(asleep)last night.

Ⅴ.微写作

翻译下列句子并连句成文，黑体部分为本单元所学知识。

1.稀有动物的存在使我们的世界丰富多彩， 充满生机。(existence)

2.但研究表明一些动物正从世界上消失。(indicate；disappear)

3.它们濒临灭绝的原因是它们不适应环境， 部分原因是人类活动。(extinct；adapt to；due to)

4.众所周知， 许多猎人靠打猎生存， 他们为了发财甚至破坏它们的栖息地。(exist on；make a fortune；destroy)

5.庆幸的是， 许多人主张政府应该采取措施来保护动物。(claim)