Question

I was walking in the street___,it began to rain A.when B.till

Answer 1

A. when

when 在这里是并列连词， 意为“其时”， 用以引出一个意想不到的动作， 强调后一分句动作的突然性

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Answer 2

till 直到

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Answer 3

选项是A

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追答

I was walking in the street when it began to rain.
=I was walking in the street and at that time it began to rain.
意思是：“我正在街上行走时，突然开始下雨”。
when在此是【突然】的意思，是并列连词。
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