现在完成时 since 能否去掉
问题描述：
现在完成时 since 能否去掉
比如I have learnt maths since 2 years ago可改为I have learnt maths 2 years
还有这道题He said that he had met her two years——.
A.before B.ago C.for 2 years D.since 2 years ago
He said that he had met her two years——.
A.before B.ago C.for 2 years D.since 2 years ago
答
不可以去掉,since表示从过去到现在的一段时间,用完成时.
去掉since,就成了过去的一个时间点,就只能用一般过去时了.