A. was sweeping B. is sweeping 15. While they 13. Our family. A. is watching _ the latest news about the huge earthquake in Japan at this time last night. B. was watching C. watched D. watches through the area. C. swept D. sweep 14. When we were enjoying a picnic, a storm suddenly. TV, a breaking news interrupted their show to announce a sudden earthquake. A. was watching B. were watching C. watched D. watch 16. A loud thunderstorm at 6 a.m. this morning. A. happened B. happens C. were happening D. was happening 17. While I for the exam, a loud noise outside me. A. was studying/distracted B. were studying/distracted C. was studying/was distracting D. studied / distracted a presentation about the effects of natural disasters at this time last week. 18. Our group A prepared B. were preparing 19. While the scientists C. was preparing D. prepare research, a sudden volcanic eruption disrupted their experiments. A. were conducting B. was conducting 20. At this time yesterday, a powerful earthquake, A. was shaking B. were shaking C. conducted D. conduct the city. C. shook D. shaken