Dưới đây là các lỗi sai và sửa đổi:

4. Almost medical doctors **have** had some training in psychology and psychiatry.
- **Sửa**: "Almost all" hoặc "Most" (nên sử dụng "Almost all medical doctors have had...").

5. Good scientists always cooperate with each **other** no matter what their nationalities are.
- **Sửa**: "each other" (sửa "each others" thành "each other").

6. Tom said that if he had to do another homework tonight, he would not be able **to** attend the concert.
- **Sửa**: "to" (thêm "to" trước "attend").

7. In Canada, **many** people speak English because they also came from England many years ago.
- **Sửa**: "many" (sửa "much" thành "many").

8. We didn't have many **pieces of knowledge** about physics.
- **Sửa**: "pieces of knowledge" (gợi ý sửa "many knowledge" thành "much knowledge" hoặc "pieces of knowledge").

9. Neither of the scout leaders knows how to trap wild animals or how to prepare them for mounting.
- **Sửa**: "knows" (sửa "know" thành "knows").

10. The Earth is the only planet with a large **amount of oxygen** in its atmosphere.
- **Sửa**: "amount of oxygen" (sửa "number of oxygen" thành "amount of oxygen").

Hy vọng những sửa đổi này sẽ giúp bạn hiểu rõ hơn!