4、如從句表示"隨時間推移"，連詞能用as，不用when 或while。

例如：As the day went on, the weather got worse.　

日子一天天過去，天氣越變越壞。

3、當(dāng)從句的動作發(fā)生于主句動作之前，只能用when 引導(dǎo)這個從句，不可用as 或 while。

例如：When you have finished your work, you may have a rest.

2、Not until …在句首，主句用倒裝。

例如：Not until the early years of the 19th century did man know what heat is.

直到19 世紀初，人類才知道熱能是什么。

Not until I began to work did I realize how much time I had wasted.

直到我開始工作，我才認識到了我已蹉跎了幾多歲月。

1、如果hardly, scarcely 或no sooner等置于句首，句子必須用倒裝結(jié)構(gòu)：

例如：Hardly / Scarcely had I got home when it began to rain.

No sooner had I got home than it began to rain.

由because , since , as , for , now that 等引導(dǎo)

例如：As the weather was fine ,we decided to climb the mountain.

第二節(jié) 實戰(zhàn)演練

由連接詞though, although, even if , even though, as 等引導(dǎo)。但要注意從句用了though主句就不能用but。

例如：Although it’s raining ,they are still working in the field.

Boy as he is , he knows what is the right thing to do.

引導(dǎo)方式狀語從句的從屬連詞有as，(just)as…so, as if (though). As引導(dǎo)的方式狀語從句通常位于句首。As在句中帶有比喻的含義，意思是“正如……， 就像…… ”。

例如：It looks as if the whether may clear up very soon.

　　　 As water is to fish so air is to man.

由that, so that…或such…that引導(dǎo)。

例如：It is such a difficult problem that nobody can work it out.

由so that… , in order that , lest , in case , for fear that 等引導(dǎo)的從句的謂語動詞常與can , may , could , might , should 等情態(tài)動詞連用。

例如：Take an umbrella in case it should rain.

Ask him to hurry up with these letters in order that I can sign them.

由連接詞as…as、than、not so…as…等引導(dǎo)。

例如：He speaks English much better than any other student in his class.