状语从句连词

学习必备欢迎下载1．时间状语从句的连词表示时间的连词有when, while, as, by the time, before, after, since, till/until, as soon as，有些名词短语也可以引导时间状语从句，如the moment, the instant, each time，有些是固定句型如： no sooner ⋯ than hardly/scarcely ⋯when。在这些连词的使用中应注意① as强调同时，也表示一边 ⋯⋯，一边⋯⋯" ，while 表示主句动作发生在从句的过程之中，要求从句谓语动词为状态动词或持续性动词，when 的使用则比较简单，相当于汉语的 "当⋯⋯时候"。如：Doing your homework is a sure way to improve your test scores, and this is especially true ____ it comes to classroom tests. A. when B. since C. before D. after ? 四个选项都表示时间，但根据主从句间的关系可以判断答案为 A。② 注意 when 的特殊句型下列句型中 when 连接的不是时间状语从句， 但考试中却常与其它时间状语从句的连词一块出题。were/was doing something when ⋯were/was about to do something when ⋯had just done something when ⋯? ③ 注意 no sooner ⋯ than ⋯.和 hardly/scarcely ⋯when句中的时态。④ 注意 not ⋯ until 中时间状语可以提前。如 ____ quite recently, most mothers in Britain did not take paid work outside the 学习必备欢迎下载home. A. Before B. Until C. From D.Since 比较常见的提前方式是将not until⋯.提至句首，后面用肯定形式，主谓倒装。本题可以改成， Not until quite recently did most mothers in Britain take paid work outside the home.这时，句子采用主谓倒装结构，应注意。⑤名词短语做连词引导时间状语从句时，如：the moment，the instant，the second，the minute都可做连词用，引导定语从句，意思是as soon as You see the lightening ___ it happens, but you hear the thunder later. A. the instant B. for an instant C. on the instant D. in an instant 能够引导时间状语从句的是名词the instant，而不是由其构成的介词短语。⑥ 注意含有时间状语从句的固定句型，如 It won't be long before ⋯ 和 It is ⋯since两类句型。 It won't be long before ...