作业帮You look pale,______have been ill for a long timeA.since B.for C.because D.yet 应该选哪个 since ,for,because 之间有什么差别?
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You look pale,______have been ill for a long timeA.since B.for C.because D.yet 应该选哪个 since ,for,because 之间有什么差别?
You look pale,______have been ill for a long time
A.since B.for C.because D.yet
应该选哪个 since ,for,because 之间有什么差别?
You look pale,______have been ill for a long timeA.since B.for C.because D.yet 应该选哪个 since ,for,because 之间有什么差别?
你have前漏写了个单词“you”,要改为：
You look pale,______ you have been ill for a long time.
选B [for 常表示根据某种现象做出判断,用于对前一分句补充说明理由.]
A.since B.for C.because D.yet
since ,for 和 because 的区别如下：
1.since（既然）语气较弱,强调已知的事实.
例：Since you can't answer the question,I'll ask someone else.
既然你回答不出这个问题,我就问别人了.
2.for（因为）的用法：
for是并列连词,表示推断的原因,或对前一分句补充说明理由.
例：It must be morning,for the birds are singing.一定是清晨了,因为鸟儿在叫.
3.because （因为）的用法：
because通常表示直接的原因.because引导的从句表示直接而明确的原因和理由,表示按因果关系的推断,语气很强,用来回答why的问题,一般位于主句之后.
例：We couldn't go out because it was too cold.因为天气太冷,我们不能外出.
A
for 不能单独放在句子前面,
可以说You look pale for have been ill for a long time
because的话应该说 because you have been ill for a long time
yet仍然,显然意思不符
选A。since
三者虽然都可以接表示原因得句子。。。但since一般跟完成时