[解析]B､C｡作并列连词时,when/while用法较为特殊,二者区别是:while表两相对照;而when表突然､在那时,常见于be about to do...when和hardly...when等句型中｡ 考点二、表示原因的连词for/because/as/since 例3.He found it increasingly difficult to read, ___ his ...
when可作并列连词,常用于引导一个突然出现的动作,意为“那时/这时……”,此时句子的形式如下:1.Somebody was doing something when…; 2.Somebody was about/ going to do something when…; 3.Somebody was on the point of doing something when…; 4.Somebody had ...
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