Dưới đây là lỗi trong các câu và cách sửa chữa:

1. **Câu:** Our new teacher explains the exercises badly than our old teacher.
- **Sửa:** Our new teacher explains the exercises worse than our old teacher.

2. **Câu:** The Spanish athlete ran fast than the other runners.
- **Sửa:** The Spanish athlete ran faster than the other runners.

3. **Câu:** My mother and my sister talked loudly than the other guests.
- **Sửa:** My mother and my sister talked more loudly than the other guests.

4. **Câu:** We walked slowly than the rest.
- **Sửa:** We walked more slowly than the rest.

5. **Câu:** That machine works good than this one.
- **Sửa:** That machine works better than this one.

6. **Câu:** I think that good health is importantly than money.
- **Sửa:** I think that good health is more important than money.

7. **Câu:** She sings beautifully than she speaks.
- **Sửa:** She sings more beautifully than she speaks.

Hy vọng các sửa đổi này hữu ích cho bạn!