X/ 

1. Remember not to forget to brush your teeth everyday. 

2. Remember not to stay up late at night. 

3. Doing morning exercises is useful. 

4. Don't forget to write a letter to me. 

5. You should iron your clothes. 

I/ 

1. I received a letter from my uncle last week. 

2. Yesterday the doctor told Nga not to forget to brush her teeth everyday. 

3. I tell my classmates about my trip to Tri Nguyen Aquarium in Nha Trang. 

4. Yesterday i had a toothache so i went to see the dentist. 

5. Dentist checks his teeth and tells him not to worry. 

6. She always gets up early to do morning exercise. 

7. Yesterday Minh felt less scared after Dr Lai had checked his teeth. 

8. Tam looks tired because she stayed up late last night.

X)1. Remember not to forget to brush your teeth everyday. 

2. Remember not to stay up late at night. 

3. Doing morning exercises is useful. 

4. Don't forget to write a letter to me. 

5. You should iron your clothes.