4. As we all know,Beijing is one of cities in the world.

   A. big   B. bigger

   C. biggest   D. the biggest

3. The population of my hometown about 30 ,000.

   A. is   B. are   C. have   D. be

2. The tree is about 10 meters.

   A. long   B. wide   C. high   D. deep

1. - What are you doing this year?

--We’re trying the pandas. They are endangered animals.

   A. to keep   B. to save

   C. keeping   D. saving

5. Stop (pollute) rivers and lakes,or we won’t have water to drink one day.

4. Dale exercisewS every day and he is becoming and (healthy) .

2. 一Why don't you like the trip?

—Because the train is too (crowd) .

1. The tiger is one of (dangerous) animals in the world.

4. A lot of animals are in d . What can we do to help them?

5. Many fish die from water p.

3. This elephant is h and strong. It can do much work for us.