I. Điền a/an
1. uniform
2. apple
3. orange
4. hours
5. book
II. Chuyển số nhiều
1. knife->
2. country->
3. leaf->
4. key->
5. tomato->
6. photo->
III. Hơn hay nhất
1. Hoa is (tall) than Lan
2. Summer the is a (hot) in year
3. She is the (careful) in my class
4. City is (crowded) than village