作业帮the company has been producing this model of machine tool( )2008.A.since B.after C.fpr D.before
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the company has been producing this model of machine tool( )2008.A.since B.after C.fpr D.before
the company has been producing this model of machine tool( )2008.
A.since B.after C.fpr D.before
the company has been producing this model of machine tool( )2008.A.since B.after C.fpr D.before
A
现在完成进行时,表示从过去某个时间点开始进行、并将继续进行下去的情况,时间多用since.