一、that 引导的宾语从句

　　that引导的宾语从句最为普遍，从句应是完整的主谓结构，且that有时可以省略，

　　如：She told me (that) she had bought a gift for me.

　　I hope that it will be cooler tomorrow.

　　常接此类宾语从句的动词有：say, think, hope, tell, see, deny, demand, suggest, propose, declare, feel, intend, insist, believe, agree, admit, expect, explain, imagine, know, report, doubt等

　　I doubt that he has the ability to do this.

　　二、what, where, when, which, who, why,

　　how等词引导的宾语从句

　　宾语从句还可由上述类似特殊疑问词的引导词引出，此时引导词作从句的主语、宾语、或状语，不可以省略

　　如：I can't understand why you feel so bitter about her manners.

　　Could you explain what has caused the delay?

　　I wonder how you managed to escape.

　　Just tell me which one you prefer.

　　此类从句的形式颇像问句，但需注意应用陈述句语序，不可倒装

　　可接此类从句的动词有：ask, say, tell, know, wonder, understand, inform, advise, decide, find, answer, suggest, show, discuss, discover等

　　三、whether /if 引导的宾语从句

　　whether / if引导的从句，表示“是否….”，whether /if虽不在从句中担当成分，但因有实际意思，不可省略，之后的从句必须是完整的主谓结构

　　如：I wonder if /whether you are interested in his paintings.

　　I can't decide whether I should go or not. (此时不能用if)

　　注：有些be+形容词的句式结构类似于宾语从句，可归入此类，如：

　　I am sure that he will come before long.

　　I'm afraid (that) you are not allowed to enter without a pass.

　　例题：

　　(1)

　　Almost all economists agree ----by trading with one another.

　　(A) nations that are gained

　　(B) nations they gain

　　(C) gaining nations

　　(D) that nations gain

　　答案：D

　　解释：谓语动词agree的宾语不完整, 因agree一词不能直接与名词词组搭配, 但可接that引导的从句, 故D以外的选项均可排除

　　(2)

　　A biologist does not merely describe organisms, but tries to learn ----act as they do.

　　(A) what causes them to

　　(B) causes them to what

　　(C) what to cause them

　　(D) what cause to them

　　答案：A

　　解释：空格处需要的是动词learn的宾语，B是谓语形式可先排除；因不符合固定词组cause somebody to do, C和D均可排除；A是what引导的宾语从句，符合题意