when we were having a meeting,the director ____the bad news by telephone.A、was telling B、was told C、could tell D、would tell请教下这道选择题里WHEN的用法和为何选用这个答案?

We were having fun in the playground when the bell We were having a party when the rain started.(改为同义句) ________ we were having a party, therain _______. We were having supper when the phone rang.We were having supper when the phone ringing.We were having supper when the phone was ringing .哪个句子是对的? We were having supper when the phone rang 改否定同上 we were having fun p_____ games in the playground when the bell rangRT when the guest arrived.we were having our supper.为什么不能用as soon as连接 We were having fun in the park when you called me 同义句 When Bob and his friends came,we were having our supper We were having lunch,when someone knocked the door (问号处填介词或副词) 用we,a,on,dinner,having,were,ship,when,the,weater,became,stormy造句 when we were having the party,i met him.为什么要过去进行时 one day,we were having lunch when a foreign boy came( )our classroom.填一个介词~! ( )we were having breakfast,he came in.A.while B.when C.after 选哪个?为什么? when we were young we were having a party when the train started 用while 改为同义句while we ---- ---- a party ,the train ---- The students in Class One were having a P.E class()we were having a math class.A.when B.while C.asD,since They _____ supper when we _____ into the room.A. are having…went B. were having…go C. were having…went D. are having…go为什么不选D the,we,having,on,were,the,playground,fun,ring,when,bell连词成句,可以改变形式