1. If Thuy didn't study English lazily, she could pass the entrance exam.
Câu điều kiện loại 2: If + S + V(past) + ....., S + would/could... + V(bare) + O.
2. Khang asked Hue what time she went to bed.
3. Linh hasn't eaten this kind of food since Duyen's wedding.
The last time + S + V(past) + O + was + time.
= S + V(past perfect) + O + since + time.
4. Hoang is a careful driver.