Here are the correct sentences based on the provided phrases and words:

### VIII. Make correct sentences from the words and phrases given:
1. We keep our bodies warm to avoid catching a cold.
2. Getting enough rest helps you concentrate on school.
3. Vitamins play an important role in our diet.
4. You should not play more computer games in your free time.
5. The doctor is asking me questions about my health problems.

### IX. Rewrite the sentence so that it contains the word in capitals:
1. Can you tell me how to get to the nearest post office? (HOW)
2. The first question in the test was less difficult than the second one. (DIFFICULT)
3. I expected my exam results to be better than they were. (THAN)
4. The bookstore is next to the grocery store. (NEXT)
5. Dave doesn't earn as much money as his wife does. (MORE)