4. A. fly ⇒ are flying

V. 1. There are four seasons in our country.

2. They are spring, summer, autumn and winter.

3. There are many flowers in the spring.

4. The days are long in the summer.

5. It's usually very cold.

VI. 1. Nam is shorter than I am.

2. The supermarket is far from my house.

3. What about visiting Ngoc Son Temple this Saturday morning?

4. They are going to go camping this Sunday.

VII. 1. London has a population of 6.3 million.

2. Mount Everest is the highest mountain in the world.

3. We're going to visit Sam Son Beach this summer holiday.

4. What is the weather like in fall?