5.用help,happen,listen,have,ask,be,plant,miss,leave,look的适当形式填空:

(1).WangHai is a good comrade.He always does his best ________others.

(2).Dig the hole big enough,or the trees can’t ___________well .

(3).It's time for class.Let's stop _______to the teacher.

(4).Her face turned red when she _______ to sing a song for all of us.

(5).She is older than Mary but ________much younger.

(6).--I can't find my keys.--Maybe you ___________ them at home.

(7).We waited in the next room while they ____________a meeting.

(8).Hurry up.You __________the train if you don't.

思考题：　　

用 send,show,turn,cost,write,fly,get,stop,see,do,hear,go 的适当形式填空

4.The policeman asked the old granny to put down her heavy box and let him ______ (carry) it for her.

3.Alice didn't hear what the teacher said just now,so she doesn't know how ____ (do) the problem.

2.Mr Smith kept on _____ (ask) the players to remember-----TEAMWORK

1.The Great Green Wall will stop the wind from ________(blow) the earth away.　　　　　

7.疑问代词/副词 (why 除外) + to do sth. 结构,可在句中作主语, 表语和宾语.　　　　

练习题：

6.在 It‘s time(for sb.)to do sth. It's kind/nice/good of sb. to do sth.

It takes sb. some time to do sth. 的句型中, 动词不定式短语作句子真正的主语.

5.在see,hear,watch,make,let等后面作宾语补足语的动词不定式应省略动词不定式符号“ to”, 但在被动句中, 应添上"to".　　　

4.在动词 decide,hope,wish,hate 等动词后应用动词不定式作宾语,而在ask, tell,want,teach 之后则用动词不定式的复合结构,即 “ask sb. to do sth.”的形式

3.在 keep,enjoy,finish,mind 等动词后采用动词的--ing 形式.