1、当先行词是不定代词all，little, few, much, anything , everything, none, nothing, no one, some等时。

He did everything that he could to help us.

who 指人，在从句中作主语、宾语或表语

whose 指人或物，在从句中作定语

that 指人或物，在从句中作主语、宾语或表语

which 指物，在从句中作主语或宾语

when 指时间，在从句中作时间状语

where 指地点，在从句中作地点状语

why 指原因，在从句中作原因状语

(1)The man (whom /who/that) my mother saw in the street is my teacher.

(2)The book which/ that tells us about the earth is interesting.

(3)She lives in a house whose windows faces south.

(4)Do you know the boy whose father is an English teacher?

(5)I have never heard such stories as he tells.

(6)I’ll never forget the day when /on which I joined the army.

(7)I won’t forget the factory where / in which my father worked.

(8)Tell me the reason why you came late.

100.You ____　 the book to me．You can keep it if you like．

　 A．can't return 　　B．needn't have returned　 C．may not return 　　D．can't have returned

巩固练习答案：

1－5 ADBAA　 　6－10 A DABD　 　　11~15 BACBC　　 16~20 ADAAC　　　 21~25 ACBBB

26~30 ABBCC　 　　31~35 DDBAB　　　 36－40 CBCDB　 　41－45 DACBD　 　46--50　 DCBBB　

51-- 55 CDAAB　　 56--60 BBCBA　　　 61--65 DCAAA　 　66--70 DDDCB　 　　71--75　 BDCDD　　

76--80 CABCD　　 81--85BCCCC　　　 86--90BADBA　　 91--95 CBBBB　　 96--100 CBACB

99.I don't know what's the m atter．The train____here an hour ago．

　 A．shall arrive 　　　B．should arrive　　　 C．should have arrived 　D．ought have arrived

98.I can't find my umbrella．I ____it at the office．

　 A．could have left 　　B．can leave　　　　　 C．should have left 　　D．shall have

97.Li Ming ____ to visit his maths teacher last night．(but I am not sure)

　 A．must have gone 　B．might have gone　　 C．might go　 　　　　D．may go

96.I didn't hear the phone．I ____　 asleep．

　 A．must be　 　　　　B．should be 　　　　　C．must have been 　　D．should have been

95. Sorry, I am late again. I ____ have taken a taxi to come here.

　 A. need　　　　　　　　 　 B. should　　　　　　　 　　 C. will　　　　　　 　 D.must

94. ---Shall I tell Li Ming about it?　 ---No, you _____, he has known-about it already.

　 A. oughtn't to　　　　　 　　　 B. needn't　　　　　 　 C. shouldn't　　　　 　　 D. mustn't

93. ---I hear you've got a set of valuable Australian coins. ____ I have a look?　　　 ---Yes, certainly.

　 A. Do　　　　　　　　　 　　　　　 B. May　　　　　　 　　　　　 C. Shall　　　　　　　　 D. Should