1. was living
- Thì QKTD : S + was/were + V-ing
- Dấu hiệu : This time last year
2. were you doing
- Thì QKTD : W-H question + Was/were + S + V-ing ?
- Dấu hiệu : at 10:00 last night
3. was writting
- Thì QKTD : S + was/were + V-ing
- Dấu hiệu : At that time yesterday
4. was learning
- Thì QKTD : S + was/were + V-ing
- Dấu hiệu : at 7:45 yesterday morning
5. were you doing
- Thì QKTD : W-H question + Was/were + S + V-ing ?
- Dấu hiệu : at this time last night
→ I , he , she , it + was
→ you , we, they + were