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since和for后面接时间,那前面的时态是不是都用现在完成时?

来源:学生作业帮 编辑:作业帮 分类:英语作业 时间:2024/05/15 11:35:32
since和for后面接时间,那前面的时态是不是都用现在完成时?
Since = 自从;从...以来
For = (表示多长时间)
如果 since 和 for 后面接时间,那么 since 前面用现在完成时或现在完成进行时,for 前面可以用一般现在时、一般过去时、一般将来时、现在完成时、现在完成进行时、过去完成时,过去完成进行时、将来完成时,比如:
I have played the piano since last year.
I have been playing the piano since last year.
I play the piano for 3 hours every day.
I played the piano for 3 hours yesterday.
I am going to play the piano for 3 hours this weekend.
I have played the piano for 2 years (now).
I have been playing the piano for 2 years (now).
I had played the piano for 2 years.
I had been playing the piano for 2 years.
By the time I reach 30,I will have played the piano for 5 years.
Since 的其他用法及用法说明,请参考《结束蹦单词时代:外教教你用连词》,中国书籍出版社.