托福備考語法指導(dǎo)：從屬連詞及真題要點解析

　　(3) A hinge joint is ------- permits the forward and backward movement of a door。

　　(A) the

　　(B) what

　　(C) those

　　(D) whose (88.10)

　　［答案］ B what = the thing that…

　　(4) Essentially， a theory is an abstract. Symbolic representation of ------- reality。

　　(A) what it is conceived

　　(B) that is conceived

　　(C) what is conceived to be

　　(D) that is being conceived of (89.5)

　?。鄞鸢福?C what = the thing that (is conceived to be…) 。答案(A)中的代詞it是多余的，因為what本身即已包含了先行詞(the thing ) 和關(guān)系代詞(that) 。答案(B)中的關(guān)系代詞that引導(dǎo)的從句不可以置于介詞的后面。

　　(5) Most of the food what elephants eat is brought to their mouths by their trunks. (93.10

　?。鄞鸢福?B what應(yīng)改為that。此句已含有先行詞food，不能再用關(guān)系代詞what。

　　5. 主句和從句

　　解題要點 主語從句是TOEEL?？级袊忌州^陌生英文文法結(jié)構(gòu)。有關(guān)主語從句的命題幾乎全部集中在structure (1-15題)中。主語從句的特點是讀起來有種頭重腳輕的感覺，而且有兩個謂語動詞。連詞That 引導(dǎo)的主語從句應(yīng)特別留意。因為That 在句中沒有任何意義，它只具有引導(dǎo)出主語從句的功能，因而很容易被忽略。

　　全真例題分析

　　(1) ------- xenon could not from chemical compounds was once believed by scientists。

　　(A) For

　　(B) It was

　　(C) That

　　(D) While (91.1)

　?。鄞鸢福?C That引導(dǎo)的主語從句。其中第一個謂語動詞could from 是從句的謂語，第二個系動was是主句的謂語。

　　(2) ------- to space travelers is high acceleration of deceleration forces。

　　(A) Danger can be

　　(B) They can be dangerous

　　(C) What can be dangerous

　　(D) While danger (93.1)

　　［答案］ C what引導(dǎo)的主語從句。What既是從句的連詞，又是從句的主語。

　　(3) ------- has been a topic of continual geological research。

　　(A) Did the continents originate

　　(B) How did the continents originate

　　(C) Have the continents originated

　　(D) How the continents originated (91.1)

　?。鄞鸢福?D How 引導(dǎo)的主語從句。

　　(4) ------- progress helps to relieve scarcities is a fact accepted by economists。

　　(A) Technological

　　(B) That technological

　　(C)Although technological

　　(D)There is technological