Question

4. Look,so many people are running out of the station. I wonder what      .

   A. is happened   B. was happening

   C. is happening   D. had happened

Answer 1

4. C

句意:看，那么多人正往車(chē)站外跑。我想知道正在發(fā)生什么事。is happened—般現(xiàn)在時(shí)的被動(dòng)語(yǔ)態(tài)；was happening過(guò)去進(jìn)行時(shí)；is happening現(xiàn)在進(jìn)行時(shí)；had happened過(guò)去完成時(shí)。根據(jù)句意可知事情正在發(fā)生，應(yīng)該用現(xiàn)在進(jìn)行時(shí)。故答案為C。