（1） that引导的主语从句句型
that引导的主语从句直接放在句首的情况较少，例如：
a.That he doesn't understand English is obvious.
b.That the world is round is a fact.
c.That the Moon itself does not give off light is common knowledge.　月球本身不发光，这是一个常识。
更常见的是用it作形式主语置于句首，而将that引导的主语从句放在句末， 例如：
d.It is obvious that he doesn't understand English.
e.It is a fact that the world is round.
f.It is common knowledge that the Moon itself does not give off light.
g.It is common knowledge that the whale is not a fish.
h.It is common knowledge that a flash of lightning is seen before a clap of thunder is heard.
i.It is a shame that you did not pass the test.
你没通过这次考试真遗憾。
因此，下列都是常见的主语从句句型：（重点内容！）
1） It is +过去分词+ that从句：过去分词可以是reported，noted，found，pointed等。
It's reported that...　据报道……
It's believed that...　人们相信……
It is generally thought that...　人们普遍认为……
It should be noted that...　应当注意……
It has been found that...　现已发现……
It must be pointed out that...　必须指出……
同样可以这么用的动词有：say，expect，know，estimate，forecast等。
2） It is +形容词+ that从句：形容词可以是clear，possible，certain，necessary等。
It is clear that...　显然……
It is possible that...　有可能……
It is likely that...　很可能……
It is natural that...　很自然……
It is certain that...　可以相信……
It is strange that...　奇怪的是……
It is fortunate that...　幸运的是……
It is necessary that...　有必要……
3） It is +名词短语+ that从句：名词短语可以是a pity，a shame，an honor，a good idea，no wonder等。
It is a pity that...　可惜的是……
It is a fact that...　事实是……
It is good news that...　……真是太好了。
It is a good thing that...　……真是件好事。
It is no wonder that...　难怪……
It is a shame that...　遗憾的是……/……真是太不像话了。
It is an honor that...　很荣幸……
It is common knowledge that...　……是常识。
It is my belief that...　我相信……
It is a miracle that...　……真是奇迹。
4） It +不及物动词或其短语+ that从句：不及物动词或其短语可以是seem，appear，turn out，come about等。
It seems that...　似乎……
It follows that...　因此……/由此可见……
It happens that...　碰巧……
It turns out that...　结果证明是……
It comes about that...　结果是……
a.It seems that you know a lot about computers.
b.It turned out that he did not steal her book.
5）其他结构：
It dawns upon/on sb. that...　某人突然想起……
It occurs to sb. that...　某人突然想起……
It makes no difference that...　……无所谓。
It doesn't need to be bothered that...　不必担忧……
It is of little consequence that...　……无关紧要。
a.It has never occurred to me that he is a thief.　我从没想到他是小偷。
b.It dawns upon me that there is a logical connection between all the things that happen in that immensely connected body of salted water that covers 71 percent of the surface of the Earth.
c.It makes no difference whether he will come or not.
（2） whether及连接代词或连接副词引导主语从句一般放在句首。
a.Several days ago, an IT company fired about 400 people overnight. The act startled the fired employees and at the same time worried the rest. Moreover, what was special about this case was that the day before the 400 were fired, they all received from their boss a gift—the book Who Moved My Cheese?.
b. What happened on September 11, 2001 will be forever etched in our memory.　9·11事件将会永远铭刻在我们的记忆中。