hour.他说他能来,但只能待一个小时。
I think it necessary that you should read English every day.
我认为你每天读英语是很有必要的。
关系代词在定语从句中作宾语、表语或在定语从句中用于there be句型时,that也可以省略。
This is the happiest day (that) I have ever spent in all my life.这是我一生中度过的最快乐的一天。
China is not the country (that) she used to be.
中国不再是以前那样。
This is the fastest train (that) there is to Shanghai.
这是去上海的最快列车。
(2)不定式符号to的省略:
①并列的不定式,前面的不定式带to,后面的to可省去,但如果两个不定式之间有对比关系时,则不可以省去to。
I told him to sit down and wait for a moment.
我告诉他坐下来等一会儿。
To go home or to stay at school during the vacation is not decided yet.假期期间回家或待在学校还没有决定。
主语和表语或主语与比较状语从句中的主语都为不定式时,to不能被省略。
To see is to believe.眼见为实。
It is better to stay here than to go home.
待在这儿比回家更好。
②某些使役动词(如make,let,have)及感官动词(如see,watch,notice,observe,hear,feel,look at,listen to等)后面作宾语补足语的不定式一定要省去to,但在被动语态中须把to复原。
People saw the little hero fall from the tall tree.
人们看到小英雄从高高的树上掉了下来。
The little hero was seen to fall from the tall tree.
小英雄被看到从高高的树上掉了下来。
③help当"帮助"讲时,后面的宾语或宾语补足语的不定式符号to可被省略,也可不省略,但在被动语态中不能省略to。
I will help (to) do it for you.我会给你帮助。
The peasants are often helped to repair tractors by the workers.农民常被工人帮助修拖拉机。
④介词but前若有动词do的任何形式,后面的动词不定式不带to。
There was clearly nothing to do but turn to the police for help.很显然除了向警察寻求帮助,没有别的办法了。
⑤主语从句中有动词do时,后面作表语的动词不定式中的to