(二)表语从句知识要点
A.引导词问题
引导表语从句的连接词有:1)that;2)whether;3)连接代词和连接副词;4)because,why;5)as if,as though;6)as。现分述如下:
1.引导词that
在口语中that多可省略。例如:
My idea is that we should have a discussion about the problem.我的想法是我们开个讨论会讨论这个问题。
that引导的表语从句多用在下列结构中:The fact/truth/chance/result/reason/cause+is that...。例如:
The fact is that you didn't finish the work on time.事实是你没有按时完成工作。
The chance is that one smoker in four will die from smoking.机率是四个烟民中将会有一人死于吸烟。
The reason why he didn't go was that he was ill yesterday.他之所以没有去是因为他昨天病了。
2.引导词whether
引导表语从句只能使用whether,不能使用连词if。例如:
问题是这个方案能否正常运作。
[误]The problem is if the plan will work smoothly.
[正]The problem is whether the plan will work smoothly.
3.连接代词(what,who,which,whose等)和连接副词(when,where,why,how等)
The town is no longer what it used to be.这个城镇已不再是过去的样子了。
The most important thing is who broke the window.最重要的是谁砸碎了窗户。
对于连接代词和连接副词引导的表语从句,同学们还要注意其语序应为陈述语序,而非疑问语序。例如:
[误]The problem is how can we get so much money.
[正]The problem is how we can get so much money.
[误]That's where was our house.
[正]That's where our house was.
4.引导词because
because也可以用于引导表语从句。例如:
We didn't have the football match.That was because it rained hard yesterday.我们没有举行足球赛,那是因为昨天下大雨。
because引导表语从句时,极易与why混淆。because用于结果已于前述、需要补述原因时,也即“先果后因”的倒序法。例如:
He didn't come to school yesterday.That was because he was ill.他昨天未来上学,那是因为他病了。(didn't come to school是结果,was ill是原因)
why则用于原因已于前述、需进一步说明其结果的情况,也即“先因后果”的顺序法。例如:
He was ill yesterday.That was why he didn't come to school.他昨天病了,那就是他之所以没有来上学的原因。(was ill为原因,didn't come to school为结果)
需要特别说明的是,在下面两个表示原因的句型中,应用that,而不能使用why或because。即:1)The reason why...is that...;2)The cause is that...。例如:
The reason why she didn't come to the party was that she hadn't received the invitation.她没有来参加晚会的原因是她没有接到请贴。
The cause of the accident was that the driver had drunk too much before driving.事故的起因是司机驾驶前喝的酒过多。
有时,The reason why...is that...句型中的the reason省略了,而主语为why引导的主语从句,此时其后的表语从句也应使用that。例如:
Why we decided to put off the meeting was that our headmaster hadn't come back from Beijing.我们之所以决定推迟会议,是因为我们的校长在北京尚未回来。
5.引导词as if,as though
as if和as though可用于look,seem,appear,feel,smell,sound,taste等动词后引导表语从句。例如:
It seems as if it is going to rain.看来天要下雨。
He looked as though he knew everything.他看上去似乎什么都知道。
6.引导词as
as有时也可用于引导表语从句。例如:
The main reasons are as follows.主要原因如下。
B.语气问题
1.在seem,look,feel,smell,sound,taste等动词后接的as if或as though引导的表语从句中,若其内容是一种假设或与事实不符,则需用虚拟语气。例如:
The elephant feels as if it were a wall.大象摸上去就像一堵墙。
When a pencil is partly in a glass of water,it looks as if it were broken.当铅笔被部分放入一杯水中,它看上去就像是断了。
2.suggestion,order,proposal,demand等名词后面的表语从句的谓语动词多用“should+动词原形”,should可省略。例如:
Their suggestion is that our output (should)be increased by 20%.他们的建议是我们的产量应当增加百分之二十。
His proposal was that we (should)put off the meeting.他的建议是我们应当推迟会议。