2014年英语六级语法精要：状语从句(3)

　　2014年英语六级考试就要来了，下面是小编为大家整理的2014年英语六级语法精要，供各位考生参考。

　　比较状语从句：

　　than, as…as…，not so as…，(not) the same as, the+比较级;

　　eg：Light travels fast than sound.

　　the+比较级：

　　eg：The sooner，the better.

　　eg：Girls are thus seen as less valuable than boys and art kept at home to do housework while their brothers are sent to school - the prophecy(预言) becomes self- fulfilling, trapping women in a vicious circle (恶性循环) of neglect.

　　(1)当……的时候：while, when, as ;

　　when：强调一件事情正在发生的时候，另外一件事情突然发生;

　　eg：When I was watching TV, my mother came back.

　　while：强调两个动作同时进行，一边……一边……;

　　eg：My father is cooking while my mother is reading newspaper.

　　as："随时间推移"

　　eg：As time went by, the days became longer and longer.

　　(2)一……就……：as soon as ,主将从现;用directly，immediately, instantly连接两个句子;一些名词如the minute，the moment, the instant也可表示;no sooner… than, hardly… when后面的句子需要倒装;

　　eg：I will write to you the moment/minute I arrived in Paris.

　　(3)特殊单词：by the time that, every/each time(使用时后面不要再加when)

　　(4)till&until：

　　① 肯定形式表示的意思是"做某事直至某时"，动词必须是延续性的; 否定形式表达的意思是"直至某时才做某事"，一般用until，动词为延续性或非延续性都可以;

　　eg: I slept until midnight.

　　Wait till I call you.

　　She didn't arrive until 6 o'clock.

　　② Until可用于句首，而till通常不用于句首，通常用于句中;

　　eg: Until you told me, I had heard nothing of what happened.

　　eg：As you sleep you pass through a sequence of sleep states—light sleep, deep sleep and REM (rapid eye movement) sleep—that repeats approximately every 90 minutes.

　　条件状语从句：

　　(1)连接词：if, once, as long as, on condition that

　　① 如果引导的条件可以实现，主将从现;

　　② 如果引导的条件和事实相反，则用虚拟语气;

　　eg：If winter comes can spring be far behind.

　　As long as it doesn't rain, we can play.

　　You can go out on condition that you wear an overcoat.

　　Modern cars are far tougher to steal, as their engine management computer won't allow them to start unless they receive a unique ID code beamed out by the ignition (点火) key.

　　原因状语从句

　　连接词：because, since, as, for ，now that, in that, owing to, due to, thanks to, because of , as a result of;

　　比较：because, since, as和for

　　1)　because语势最强，用来说明人所不知的原因，回答why提出的问题。当原因是显而易见的或已为人们所知，就用as或 since。

　　I didn't go, because I was afraid.

　　Since /As the weather is so bad, we have to delay our journey.

　　2)　由because引导的从句如果放在句末，且前面有逗号，则可以用for来代替。但如果不是说明直接原因，而是多种情况加以推断，就只能用for。

　　He is absent today, because / for he is ill.

　　He must be ill, for he is absent today.

　　now that ：既然;

　　in that :因为，通常只能放在句中，强调重要的，唯一的原因;

　　eg：Now that this semester is finished, I am going to rest a few days and take a trip.

　　Human beings are different from animals in that human can speak and think.

　　owing to, due to, thanks to, because of , as a result of等短语后面只能接词或短语，不能接从句;