21. has taught / graduated ( HTHT - since )

22. don't know ( HTĐ ) / hasn't spoken ( HTHT - for a long time - S là she - dùng has - V3 )

23. circles ( HTĐ - every 365 days - S là the earth - V thêm s/ es )

24. How ..... have you seen ( HTHT - câu hỏi - đảo have lên đầu ) / gone ( HTHT - since )

25. is increasing ( The number + N số nhiều + V số ít )

26. goes ( HTD - always - S là số ít - V thêm s/es / is travelling ( HTTD - hành động đi xe bus chỉ xảy ra trong hôm nay - S là she - dùng is - Ving )

27. are ( we là số nhiều - dùng are )  / have been ( HTHT - for - S là we - Dùng have - V3 )

28.Have you ever seen .... ? / have since / was 

29. hasn't come ( HTHT - yet - S là she - dùng has - V3 )

30. have seen ( HTHT - several times - S là I - dùng have )

31. finishes ( HTĐ - Tôi sẽ đợi cho đến khi anh ấy hoàn thành tiểu thuyết của mình ) 

32. have ever seen 

33. hasn't finished ( HTHT - yet - S là he - dùng has - V3 ) 

21 have taugh / graduated

22 don't know / hasn't spoken

23 circles

24 have you seen / went 

25 increased

26 goes / is traveling

27 are / have been

28 Have you ever seen 

-> have seen / was

29 hasn't come

30 have seen 

31 finished

32 have evver seen

33 hasn't finished

chúc bạn học tốt ^^