这种句子,你可以用“when或者while”来引导.但是要注意,以when引导的时间状语从句,主句要用过去进行时,从句用一般过去时.while刚好相反,主句用一般过去时,从句用过去进行时.
I was walking down the street,when the UFO arrived.
While I was walking down the street, the UFO arrived.
这种句子,你可以用“when或者while”来引导.但是要注意,以when引导的时间状语从句,主句要用过去进行时,从句用一般过去时.while刚好相反,主句用一般过去时,从句用过去进行时.
I was walking down the street,when the UFO arrived.
While I was walking down the street, the UFO arrived.