giúp nhanh với ạ 1, at this time yesterday i _____ a video conference from my office a, attended b, was attending c, will attend d, will be attending 2, when you came in , i _____ a video conference from my office a, attended b, was attending c, will attend d, will be attending 3, at this time next week i _____ a video conference from my office a, attended b, was attending c, will attend d, will be attending 4 when you come next week , i _____ a video conference from my office a, attended b, was attending c, will attend d, will be attending 5, currently i _____ a video conference from my office so can you call back later ? a, was attending b, am attending c, will be attending d, attend 6, oh , the earthquake is shaking so violently . those old houses ____ soon a, are collapsing b, will be collapsing c, are going to collapse soon d, will collapse