when作并列连词 高考频度：难易程度：1. (2017天津)I _down to London when I suddenly found that I was on the wrong road.A. was driving B. have driven C. would drive D. drove【参考答案】A 2. Tom was about to close the window _ his attention was caught by a bird.A. whenB. ifC. andD. till【参考答案】A【试题解析】句意：汤姆正要关窗子，这时一只小鸟引起了他的注意。be about to do sth. when.即将做某事，就在这时。【归纳拓展】 be about to. when.句式表示正要这时(突然)。when在此为并列连词，意为就在这时(突然)。I was about to say when you interrupted me. 我正要说话的时候，你插嘴了。I was about to go out when the telephone rang. 我正要出去，电话铃响了。 be doing sth. when.正在做某事，就在这时 be going to do sth./on the point of doing sth. when.正在做某事，就在这时 had just done sth. when.刚刚做完某事，就在这时We were having a meeting when someone broke in. 当时我们正在开会，突然有人闯了进来。She was on the point of watching TV when there was a power failure. 她刚要看电视，这时突然停电了。I had just gone to bed when the telephone rang. 我刚刚上床睡觉，突然电话铃响了。1. I was about to cook my supper _ the telephone rang, but it hung up _ I could answer it.A. while; whenB. when; asC. as; afterD. when; before2. The agent was about to sign his name on the document_, to our surprise, a stranger broke in to prevent him.A. whileB. whenC. asD. until3. I was taking a walk in the park bathing in the sun _ something unusual caught my attention.A. whileB. thatC. whenD. as4. She was about to go out _ the doorbell rang.A. while B. as C. then D. when5. 句型转换She was thinking about the problem and at this time Tom patted her. She was thinking about the problem _ Tom patted her.The pupils were on the point of listening to the tape and when the teacher came in.The pupils _ the tape _ the teacher came in.1. D【解析】句意:我正要去做晚饭,这时电话响了，但我还没来得及接，电话就挂了。be about to do.when.正要做，这时；before作连词，意为在之前，没(做)之前。3. C【解析】考查状语从句。根据句意和分析句子结构可知，这里用be doing sth. when表示正在做某事时突然，因此选C。4. Dbe about to do.when.，意为“正要这时突然”。5. when were on the point of listening/were about to listen to；when贵有恒何必三更眠五更起，最无益只怕一日曝十日寒。_