原因状语从句-课件【PPT演讲稿】

arth is traveling around the sun . (5) 表示“……的原因是因为……”这一意义时,一般要用 The reason why … is that …如: The reason why he e is that he is ill. 他不关于 since since 引导的原因状语从句一般放于主句之前, 表示已知的、显然的理由(通常被翻译成“既然”),较为正式,语气比 because 弱。例如: Since you are free today, you had better help me with my mathematics . 既然今天你休息, 你最好帮我补习数学。 since 可用于省略句,而其它不能。如: Since so, there is no more to be said. 关于 as as引导原因状语从句时表示附带说明的“双方已知的原因”,语气比 since 弱,较为正式,位置较为灵活(常放于主句之前)。例如: As it is raining, you ’ d better take a taxi . 既然在下雨, 你最好乘出租汽车。 I went to bed early, as I was exhausted. 我睡得早, 因为我筋疲力尽了。关于 for (1) for 是并列连词(其他为从属连词),它有时可表示因果关系(只能放在主句之后)是对前面分句的内容加以解释。如: It rained last night, for the ground is wet this morning. (2) for “因为,由于”表明附加或推断的理由,引导的分句前常有逗号。 for 分句不放句首.是用来附带解释或说明前一分句的原因和理由。例如: Day breaks, for the bird sings.