46.如此…...以至于...…

　　so/such...that...如此......以至于......(that引导结果状语从句)

　　so是副词，后接形容词或副词

　　such是形容词，后接名词

　　Tom is such a clever boy that he cananswer the question.=Tom is so clever a boy that he can answer the question.

　　汤姆如此聪明，以至于他能够回答这个问题。

　　The box is so heavy that I can’t carry it.

　　这个箱子如此重，以至于我搬不动它。

　　注意：在名词前有many/much/few/little这些词修饰时，要用so…that...。

　　47.当......的时候

　　when+延续性/短暂性动词

　　while+延续性动词(多用进行时)

　　When I was watching TV，he came in.

　　=When he came in，I was watching TV.

　　While I was in Shanghai，I visited him.

　　48.at the age of和when引导的时间状语可以互换

　　I began to play football when I was five years old.

　　=I began to play football at the age of five.

　　我五岁时开始踢足球。