it用作形式宾语的用法
一、基本用法
当
不定式、动名词、
从句等复杂成分用作宾语且其后跟有
宾语补足语时，通常会在宾语补足语前使用形式宾语it，而将真正的宾语移至句末，其基本结构为“动词+it+宾语补足语+不定式(动名词或从句)”：
I find it difficult to do the job well. 我发现做好这件事不容易。
I think it best that you should stay here. 我认为你最好住这儿。
We think it no use complaining. 我们认为抱怨是没有用的。
二、几种特殊的形式宾语
通常意义的形式宾语主要见于真正宾语为不定式、动名词、从句等且其后跟有宾语补足语时的情形，即用于“动词+it+宾语补足语+真正的宾语”这样的结构，但以下几类形式宾语却比较特殊，其后没有宾语补足语。
1. 动词+ it + that-从句
I like it that you came. 你来了，我很高兴。
I take it (that) he will
come on time. 我认为他会准时来的。
You can put it that it was arranged before. 你可以说这是以前安排的。
Rumor has it that the defence minister will soon resign. 据传闻，
国防部长不久就要辞职。
【注】能用于此结构的动词不多，常见的有 have, take, put, like 等。(from
www.yygrammar.com)
2. 动词 + it + when (if)-从句
I dislike it when you whistle. 我不爱听你吹口哨。
We really appreciate it when she offered to help. 她来帮忙了，我们十分感激。
I’d prefer it if I didn’t have to do so much work. 要是我不必做那么多工作，好就太好了。
【注】能用于此结构的动词不多，常见的有 enjoy, hate, love, like, dislike, appreciate, prefer 等。
3. 动词 + prep + it + that-从句
See to it that you’re not late again. 注意千万不要再迟到。
Look to it that this doesn’t happen again. 注意不要再发生这种事。
I can’t answer for it that he will come. 我不能保证他会来。
You may rely on it that he’ll come to meet you. 你放心，他会来接你的。
【注】能用于此结构的动词不多，常见的有see to, look to, insist on, stick to, depend on, answer for 等。
4. 动词 + it +
介词短语+ that-从句
I owe it to you that I am still alive. 多亏有你我才仍然活着。
I took it for granted that he would help us. 我认为他会帮助我们的。
【注】能用于此结构的动词不多，常见的有take it for granted, bring it to sb’s attention, owe it to sb 等。
it形式宾语的考点说明
1. it用作形式宾语的基本用法
当不定式、动名词、从句等用作宾语且其后跟有宾语补足语时，就应在宾语补足语前使用形式宾语，而将真正的宾语移至句末：
We found it difficult to persuade her. 我们发现很难说服她。
He makes it a rule to get up before dawn. 他习惯于天亮前起床。
I think it very strange that he goes out walking almost every night. 我认为他几乎每晚都出去散步是很奇怪的。
2. 几种特殊的形式宾语
通常意义的形式宾语主要见于真正宾语为不定式、动名词、从句等且其后跟有宾语补足语时的情形，即用于“动词+it+宾语补足语+真正的宾语”这样的结构，但以下两类形式宾语却比较特殊，其后没有宾语补足语。如：
(1) 由于介词后通常不能直接跟that从句作宾语，有个别特殊结构就在介词后先接it作形式宾语，再跟that从句。如：
You may depend on it that he will turn up
in time. 你可以相信他会及时赶到的。
I can’t answer for it that the boy is honest. 我不能保证这个男孩是诚实的。
I’ll see to it that all these letters will be sent to the post before twelve. 我将注意让所有的信件在12点以前送到邮局。
【注意】① 在其他情况下解决介词后跟that从句的办法是借用the fact作宾语。如：
They were worried over the fact that you were sick. 他们为你生病发愁。
② 个别介词(主要是but和except)也可接that从句作宾语。如：
I know nothing about him except that he lives next door. 我只知道他住在隔壁，其他的就不知道了。
(2) 有的动词由于通常只用作
及物动词，当它们后接if从句或when从句，通常应先在动词后接it作形式宾语。如：
She won’t like it if you arrive late. 她不喜欢你迟到。
He hates it when people use his bike. 他讨厌别人用他的自行车。
I hate it if you say such things in public. 我讨厌你在大庭广众之下说那样的事。
I’d prefer it if I didn’t have to do so much work. 要是我不必做那么多工作，那就太好了。
I would appreciate it very much if you would help me with it. 如果你能帮助我做这事，我会十分感激。
【注意】能这样用的动词不多，主要的有enjoy, like, dislike, love, hate, prefer, appreciate等表示情绪的动词。而且高考对此也有所考查，请看一道高考真题(答案选A)。如：
I hate ______ when people talk with their mouths full.
A. it B. that C. these D. them
(3) 用于 have it that(说，认为)，take it that(认为)等个别固定表达中。如：
I take it (that) you agree. 我以为你同意了。(from
www.46english.com)
Report has it that about 30 people were killed in the accident. 据报道，在这次事故中大约有30人丧命。