I have known her ___ since she was a freshman.

B
ever since [副／介词词组]
从……起一直到现在；此后一直；从那时到现在
He went to Beijing in 1980 and has lived there ever since.
他1980年去了北京,此后一直住在那里.
I've been here ever since yesterday.我自昨天到现在一直在这儿.
【典型考题】 I have not seen him ______ he left.
A．ever since B．after
C．before D．until
答案A.句意：自他离开后,我一直没见过他.如果用after,before或until时,表达一个具体的时间点,主句都不用现在完成时,只有 ever since要求主句用现在完成时,表示从他离开到现在这段时间里的情况.
【记忆技巧】在ever since里,ever起加强语气的作用,它本身没有什么词义,since表示从……开始直到现在,它可表示一个时间段,例如：ever since last night自昨晚以来一直到现在.ever since要求其主句里用到现在或过去完成时,并用延续性动作或瞬间动词否定式.

ever
ever since从那以后

B

I have known her _ever__ since she was a freshman

B

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