1.　　 comes

46、The windows of our lab ___________ (clean) once a week. 47、Our teacher ___________ (join) the party twenty years ago. 48、The boys___________ (have) a basketball match now. Let’s ___(go) and _____(watch). 49、She___________ (work) in this factory for ten years. 50、 “What makes you ___________ (think) I’m a farmer?” the Frenchman asked.

21、Let’s _______(carry) the boxes to the house. 22、Yesterday she ______　(want) very much to see the film, but she couldn’t　 __(get) a ticket. 23、I _________(write) to you as soon as I get to Shanghai. 24、Mike ___________(visit) several places since he came to Beijing. 25、He ___________ (write) four letters to his wife every month. 26、Don’ t make any noise, Grandma 　___________　(sleep). 27、His aunt ___________ (do) some cooking when he came in . 28、When they 　___________　(reach) the station, the train had already left. 29、There 　___________　(be) a meeting next Monday. 30、We ___________ (know) each other since our boyhood.. 31、Sometimes my father ___________ (come) back home late. 32、They ___________ (have) an English evening next week. 33、I’m very glad___________ (hear) that. 34、Wei Fang isn’t here. She ___________ (go) to the reading-room. 35、The story ___________ (happen) long ago. 36、They ___________ (visit) the History Museum last week. 37、Zhang Hong ___________ (make) many friends since she came to Paris. 38、She ___________ (go) to the cinema with her classmates tomorrow evening39、Stay here, bag. Don’t go out. It ___________(rain) now. 40、Li Ping___________ (write) a composition every week. 41、The scientist ___________ (give) us a talk yesterday. 42、My parents ___________ (live) in Beijing since 1949. 43、Look! The young worker___________ (show) the students around the factory now. 44、They ___________ (build) a new bridge over the river next year. 45、The students___________ (clean) their classroom tomorrow.

1、I’ ll give the book to him as soon as he ________ back. 2、Has the baby ________ crying yet? (stop) 3、I don’ t know whether Mother　__________ me to Beijing next month.(take) 4、She _______ on her coat and went out. (put) 5、 “What are they doing?”　 “They　__________ ready for the sports meeting.” (get) 6、The boy asked his mother ________him go and play basketball.(let) 7、I’m sorry to keep you ____________ for a long time. (wait) 8、It ________ (take) him half an hour　_______ (finish) his homework yesterday. 9、If it ________ an interesting film, we’ll see it tomorrow. (be) 10、They usually ________ (do) their homework after supper. 11、Listen! Who _____________(sing) in the next room now? 12、__________(be) your parents in Shanghai last year? 13、Mr. Yu _____________(teach) us maths since 1982. 14、They will have a trip to the Great Wall if it _________ (not rain) tomorrow. 15、Li Ming often _________ (listen) to the radio in the morning. 16、A: “Father, may I go out and play football?”　 B: “_____you ____(do) your homework?” 17、All the people in the town are glad ______(hear) that a famous musician 　　　 ___ a concert this Saturday evening.( give) 18、Our teacher told us if it _____(not snow) we would visit the Science Museum the next day. 19、They often 　_______ (play) football in the afternoon. 20、A: What’re you doing Dad?　 B: I　_______　(mend) the radio.

20.时态一致

　 1) 如果从句所叙述的为真理或相对不变的事实，则用现在时。例如：

　 At that time, people did not know that the earth moves. 那时，人们不知道地球是动的。

　 He told me last week that he is eighteen. 上星期他告诉我他十八岁了。

　 2) 宾语从句中的，助动词ought, need, must, dare 的时态是不变的。例如：

　 He thought that I need not tell you the truth. 他认为我不必告诉你真相。

19. 现在进行时代替将来时

1) 表示即将发生的或预定中计划好的活动。例如：

　 Are you staying with us this weekend? 和我们一起度周末好吗?

　 We are leaving soon.　 我们马上就走。

2) 渐变动词，如get, run, grow, become, begin以及瞬间动词die等。例如：

　 He is dying. 他要死了。

18. 一般现在时代替现在进行时。

在Here comes…/There goes…等句型里，用一般现在时代替现在进行时。例如：

　 There goes the bell. 铃响了。

17. 一般现在时代替现在完成时

1) 有些动词用一般现在时代替完成时，如hear, tell, learn, write , understand, forget, know, find , say, remember等。例如：

　 I hear (= have heard) he will go to London. 我听说了他将去伦敦。

　 I forget (=have forgotten) how old he is. 我忘了他多大了。

2) 用句型 " It is … since…"代替"It has been … since …"。例如：

It is (= has been) five years since we last met. 从我们上次见面以来，五年过去了。

16. 一般现在时代替一般过去时

1 ) "书上说"，"报纸上说"等。例如：

　　 The newspaper says that it's going to be cold tomorrow. 报纸上说明天会很冷的。

　2) 叙述往事，使其生动。例如：

Napoleon's army now advances and the great battle begins.拿破仑的军队正在向前挺进，大战开始了

15. 一般现在时代替一般将来时

When, while, before, after, till, once, as soon as, so long as, by the time, if, in case (that), unless, even if, whether, the moment, the minute, the day, the year, immediately等引导的时间状语从句，条件句中，用一般现在时代替将来时。例如：

　He is going to visit her aunt the day he arrives in Beijing. 他一到北京，就去看他姨妈。