Dưới đây là ví dụ về các dạng khẳng định, phủ định và nghi vấn cho một số câu trong bài tập của bạn:

1. **Khẳng định:** They decided to leave soon.
- **Phủ định:** They didn’t decide to leave soon.
- **Nghi vấn:** Did they decide to leave soon?

2. **Khẳng định:** There were many homeless people here ten years ago.
- **Phủ định:** There weren’t many homeless people here ten years ago.
- **Nghi vấn:** Were there many homeless people here ten years ago?

3. **Khẳng định:** Tom’s grandfather used to be a soldier.
- **Phủ định:** Tom’s grandfather didn’t use to be a soldier.
- **Nghi vấn:** Did Tom’s grandfather use to be a soldier?

4. **Khẳng định:** I often went to school on foot three years ago.
- **Phủ định:** I didn’t often go to school on foot three years ago.
- **Nghi vấn:** Did I often go to school on foot three years ago?

5. **Khẳng định:** The cat wanted to eat yesterday.
- **Phủ định:** The cat didn’t want to eat yesterday.
- **Nghi vấn:** Did the cat want to eat yesterday?

6. **Khẳng định:** The train arrived late yesterday.
- **Phủ định:** The train didn’t arrive late yesterday.
- **Nghi vấn:** Did the train arrive late yesterday?

7. **Khẳng định:** There was something left in the fridge.
- **Phủ định:** There wasn’t anything left in the fridge.
- **Nghi vấn:** Was there anything left in the fridge?

Hy vọng những ví dụ trên sẽ giúp bạn hoàn thành bài tập một cách chính xác!