Writers, especially beginning writers, are often cautioned against using passive voice in their writing because its use slows down the pace.
由于被動(dòng)語(yǔ)態(tài)會(huì)影響節(jié)奏，作者們(特別是初學(xué)者)經(jīng)常被警告不要使用它。

Another construction that can make your writing plod is the dummy subject.
還有一種結(jié)構(gòu)也會(huì)讓你的文章變得拖沓，它就是虛主語(yǔ)。

When we use the words?it?and?there?to begin a sentence without a referent (a noun the pronoun is referring to), we’re using a dummy subject.
虛主語(yǔ)是指句子開(kāi)頭的it或there沒(méi)有指代物（it、there指代的名詞）。

In this pair of sentences:
下面兩個(gè)句子中：

I went to see?Fantastic Four 2?over the weekend. It was fun, but mostly forgettable.

“It” refers to the movie?Fantastic Four 2.?The pronoun has a referent.
It指代電影《神奇四俠2》。這個(gè)代詞有指代物。

In this sentence, however:
但這個(gè)句子里：

It is apparent that oil reserves will be exhausted by 2050.

“It” has no referent, and is therefore a dummy subject.
It沒(méi)有指代物，因此它是虛主語(yǔ)。

The same thing happens frequently with?there:
這種情況也經(jīng)常發(fā)生在there開(kāi)頭的句子上：

There are several ways in which you could begin.
There are five stages of grief.

Dummy subjects are just one of many problems that weaken your writing by making it vague, fuzzy, and indefinite. The sentences above can be reconstructed with stronger, more definite subjects:
虛主語(yǔ)是讓你的文章變得含糊不清的諸多原因之一。上面的句子可以用更有力、更明確的主語(yǔ)加以改寫(xiě)：

Some experts warn that our oil reserves will be exhausted by 2050.
You could begin in one of the following ways: (followed by a list).
Elisabeth Kubler-Ross identified five stages of grief in her book?On Death and Dying.

In general, unless you don’t know who is performing an action, or you want to emphasize the action of the sentence for some reason, you should avoid dummy subjects.
通常情況下，除非你不知道動(dòng)作由誰(shuí)做的，或是出于某種原因想要強(qiáng)調(diào)動(dòng)作本身，否則你應(yīng)該避免使用虛主語(yǔ)。

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