1. I have two grammars, ______are of great use.

　　A. all of which

　　B. either of which

　　C. both of that

　　D. both of which

　　2. I want to use the same tools _______used in your factory a few days ago.

　　A. as was

　　B. which was

　　C. as were

　　D. which

　　3. Is _______ some German friends visited last week?

　　A. this school

　　B. this the school

　　C. this school one

　　D. this school where

　　4. I have bought two ball pens, _______ writes well.

　　A. none of them

　　B. neither of them

　　C. neither of which

　　D. none of which

　　5. All that can be eaten _______ eaten up.

　　A. are being

　　B. has been

　　C. had been

　　D. have been

　　答案解析：

　　1. D. 主句中的two表明不能選A.從句中的are表明不能選B. both of which用來(lái)引導(dǎo)非限制性定語(yǔ)從句.

　　2. C. as引導(dǎo)定語(yǔ)從句時(shí)通常構(gòu)成such…as或the same…as固定搭配，其中such和same修飾其后的名詞，as為關(guān)系代詞，指代其前的名詞引導(dǎo)定語(yǔ)從句。as在從句中可以作主語(yǔ)、表語(yǔ)或賓語(yǔ)。本題中as作從句的主語(yǔ).

　　3. B. 為便于理解，改寫(xiě)本句話：This is the school that some German friends visited last week. 不難看出，作表語(yǔ)的the school是先行詞。that引導(dǎo)了定語(yǔ)從句，因?yàn)閠hat同時(shí)又作visited的賓語(yǔ)，所以被省略了。其它選項(xiàng)結(jié)構(gòu)不對(duì)。

　　4. C. 因?yàn)槭莟wo ball pens, 并且定語(yǔ)從句的謂語(yǔ)writes是單數(shù)概念。因此，C是正確選項(xiàng)。

　　5. B. 本句話中，主句的主語(yǔ)是all, 為抽象概念。因此，其謂語(yǔ)應(yīng)用單數(shù)的has been。關(guān)系代詞that引導(dǎo)定語(yǔ)從句，并在從句中作主語(yǔ)。