21. is raining - stops
⇒ Thì HTTD : S + am/ is/ are + V-ing
⇒ Thì HTĐ : S + V(s/es)
22. were watching - failed
⇒ Thì QKTD : S + was/were + V-ing
23. stayed - had lived
⇒ Thì QKHT : S + had + VpII
24. sat - were being repaired
⇒ Câu bị động thì Quá khứ tiếp diễn : S + was/were + being + P2
25. turned - went - had forgotten
26. has changed - came
⇒ Dấu hiệu thì HTHT : since
27. were talking - started - broke
⇒ While / when / as + Quá khứ tiếp diễn, quá khứ đơn
28. had done
⇒ Thì QKHT : S + had + VpII
29. has been standing
⇒ Câu bị động thì HTHT : S + have/has + been + P2
30. have spent - got
⇒ Dấu hiệu thì HTHT : since