21 C more healthy ⇒ healthier

22 D especial ⇒ especially

23 A eat ⇒ to eat

24 D on ⇒ during

25 C to do => doing

People who live a healthy lifestyle tend to be more healthy,live longer and are happier

⇒ more healthy⇒ healthier 

Ở dạng so sánh hơn,healthy ⇒healthier  chứ không phải more healthy

You should avoid heavy meals in the summer months , especial during hot days

⇒ especial ⇒ especially 

It is important eat variety of good at each meal

⇒  eat⇒ to eat

Sau tính từ important động từ thêm to vào trước nó

Eating breakfast is very imfortand because it gives you energy on the day

⇒ on⇒ during 

The best way to stop yawning at boredom is to do something interesting

⇒ to do ⇒doing