过去进行时练习题二、 用动词的适当形式填空。1. While we _ (wait) for the bus, a girl _ (run) up to us.2. I _ (telephone) a friend when Bob _ (come) in.3. Jim _ (jump) on the bus as it _ (move) away.4. We _(test) the new machine when the electricity _(go) off.5. She _ (not want) to stay in bed while the others _ (all, work) in the fields.6. While mother _ (put) Cathy to bed, the door bell _ (ring)
