1. It was the best performance I have ever seen. (Sửa "perform" thành "performance")
2. Unfortunately, the fire was discovered soon after it had started. (Đúng)
3. He's always done his job really well. (Sửa "done" thành "done")
4. Lan failed the exam because of her laziness. (Sửa "lazy" thành "her laziness")
5. The road was too narrow, so they had to widen it. (Sửa "wide" thành "widen")
6. Football is one of the most popular sports in Vietnam. (Đúng)
7. We always guarantee the safety of our passengers. (Sửa "the safe" thành "the safety")
8. It hasn't rained for a long time, so there's a shortage of water now. (Đúng)
9. I don't earn enough money to buy new clothes regularly. (Thêm "ly" vào "regular")
10. The main square was crowded with people. (Sửa "crowd" thành "crowded")
11. Ao Dai is the traditional costume of Vietnamese women. (Thêm "the" trước "traditional costume")
12. I had great difficulty in learning a foreign language. (Sửa "difficult" thành "difficulty")
13. To me, health is more important than money. (Sửa "importance" thành "more important")
14. I usually feel sleepy after lunch. (Sửa "sleepily" thành "sleepy")
15. Pam will always support you. She's the most reliable person I know. (Sửa "unreliable" thành "reliable")

CÓ THẮC MẮC GÌ THÌ CỨ HỎI LẠI MÌNH Ạ