B 有时候可以用it 作形式宾语，而把真正的宾语从句放在后面。
Bad: I thought that he could finish this job in just two hours impossible.
Good: I thought it impossible that he could finish this job in just two hours.
Bad: He left whether we should continue this project to my judgment.
Good: He left it to my judgment whether we should continue this project.
C 带有宾语从句的复合句的否定形式一般是否定主句。
Bad: I think he doesn't like the English teacher.
Good: I don't think he likes the English teacher.
D 主句一般过去时态，从句也要用过去时态；具体细节请看第一部分。
False: He wanted to know why he is crying in the corner.
Right: He wanted to know why he was crying in the corner.
宾语从句的点点滴滴 宾语从句是英语复合句中的其中非常重要的从句之一。它是用一个句子做另一个句子的宾语，将这个句子叫做宾语从句。宾语从句做介词或及物动词的宾语。现在从下列三个方面总结归纳如下：
一，引导词
A,由that 引导的陈述句性的宾语从句，在很多动词如say, think, wish , hope, see, believe, agree, expect, hear , feel等动词后。连词that只起连接作用，在从句中不做句子的成分，也无词汇意义，在口语中常被省略，但在大多数情况下还是以不省为好，特别是在笔语中。
例：I told him that he was wrong.
l在think,believe, suppose, expect等动词引起的宾语从句中，有时谓语尽管是否定意义，却不用否定形式，而将think 等动词变为否定形式。
例：I don't think you are right. (我认为你做的不对)
l在许多带有复合宾语的句子中，that引导的宾语从句经常移到句子的后面，而用it做形式宾语。
例：We think it wrong that he told a lie to everyone (我认为他向每一个人撒谎是错误的)
B,由连词if、 whether 引导的表示"是否…"的宾语从句。Whether,if 在从句中不做句子的成分，一般情况下，whether和if 可以替换。
例：I don't know if/whether he will come tomorrow.
The teacher asked if/whether we had finished the experiment.
l在介词后面的宾语从句中不用if引导
例：Everything depends on whether we have enough money。
l宾语从句中有or not时不用if引导.
例：I don't know whether the movie star will come or not.
l和不定式连用作宾语时不用if引导.
例：Whether to go there or not hasn't been decided.
C,由wh-引导的宾语从句。连接代词who,whom,whose, what, which,和连接副词when, where, why, how 等连接的宾语从句，它们在句中即有连接从句的作用，又在句中充当句子的成分。
例：Do you know which film they are talking about? (which做定语)
I don't know where he lives. (where 做地点状语)
二，宾语从句的语序，
宾语从句从句的语序必须是陈述语序，即连接词+主语+谓语+其他成分
例：I believe that they will come soon.
He asked me whether I was a teacher.
They wanted to know what they can do for us.
二，宾语从句的时态。joozone.com