4.

1.Because everyone suffers from common cold at some time or other.

2.No,it isn't.

3.It help people relieve the symtons.

4.They drink lot of hot water with sugar,lemon juice.

5.Because it helps provide with a lot of Vitamin C.

5.

1.did you do

2.went

3.didn't go

4.were

5.speaks

6.to help

7.have been

8.to come

9.write/were

10.will study

11.eat

12.stay

6.

1.There are ten dogs in their kennel.

2.My grandma is the oldest in my family.

3.Thuy is fatter than Tung.

4.I enjoy eating sandwich so much.

5.Because the soup is hot,I can't eat it now.

7.You should go to see the doctor.

8.Ha Noi is smaller than Ho Chi Minh City.

9.You should eat less meat and more vegetables.

B4:

1. Because everyone suffers from the common cold at some time other.

2. No, it isn't.

3. It can make you cough less, make you feel better, and stop your nose ruunning for a while.

4. People also drink a lot of hot water with sugar and lemon juice.

5. Because it helps provide them with a lot of vitamin C.

B5: 

1, did..........do

2, went

3, didn't come

4,  was

5, speaks 

6, to help

7, have been

8, to come

9, write, were

10, will study

11, eat

12, stay

B6

1. Their kennel have ten dogs.

2. My grandma is the oldest member in my family.

3. Thuy is fatter than Tung 

4. My favourite food is sandwich.

5. Because the soup is hot, I can't eat it now.

7. You should apply sunscreen.

8. Hanoi is not as large as HCM city.

9. I advise you to do exercise.

Xin ctlhn