=>
1. has failed
-> three times (HTHT, S have/has V3/ed)
2. established
-> in 1916 (QKĐ, S V2/ed)
3. have they lived/moved
-> how long + HTHT : bao lâu?
-> two years ago (QKĐ)
4. have finished
-> so far (HTHT)
5. am studying
-> now (HTTD, S is/am/are Ving)
6. did you buy/bought
-> thì QKĐ, Did S V? (yesterday)
7. Have you ever been/haven't been
-> ever/yet (HTHT)
8. volunteers
-> once a week (HTĐ, S Vs/es)
9. to help
-> volunteer to V : tình nguyện làm gì
10. donating
-> suggest Ving : đề xuất, gợi ý