Unit 7一、 用括号里的词的适当形式填空。1. If Marcia _(live) alone, she _ (keep) a pet parrot.2. Flowers _ (die) if you _( not water) them for a long time.3. If pandas _(have) no food, they _ (die).4. She _ (not go ) to the party unless you _ (invite) her.5. If spring _(come), the trees _(turn) green.6. If you _(put) sugar into water, it _(disappear).7. If you dont water the plant in such hot weather for a long time, it _(die).8. The Sun _(shine) brightly if there are no clouds in the sky.9. If there is a lightening, a thunder (雷声)_(come) later.10. If you work harder, you _(pass) the exam.11. The dog _(think) you are friendly if he waves his tail to you.12. If I can see the file(文件)， I _(know) how important it is.二、 用if 或unless填空。1. My baby sister doesnt cry _ she feels hungry.2. I run every morning _ it doesnt rain.3. I run every morning _ the bad weather stops me.4. _ you dont do any exercise, you will get fatter.5. You mustnt cross the road _ the traffic light turns red.三、 选择题。1. If you _ to the party, you _a great time.A. will go, will have B. go, have C. go, will D. will go, have2. Ill give the book to him if he _ here next Sunday. A. will come B. comes C. is coming D. came3. If you _ the vase, it _ into pieces. A. drop, will fall B. will drop, falls C. will drop, will fall D. drop, falls4. You wont get high marks _ you study hard. A. if B. unless C. after D. though5. If you _ metal, it _. A. heat, melt B. heat, will melt C. heat, melts D. heats, melts6. If he _, he _ there on time. A. runs, will get B. runs, gets C. will run, gets D. will run, will get7. If you _ a wine glass, it _. A. will drop, will break B. drop, will break C. will drop, breaks D. drop, break四、完成句子。1.如果鱼离开了水就会死。A fish _ if it _ out of water.2. 如果你把水烧开（boil）,有些水会变成水蒸气。If you _ water, some of it _ into steam.3.如果你吃得太多， 你会觉得很饱。You _ very full if you _ too much.2