You should put ________ on your lips to protect them from sun, wind, etc.

• Correct answer: B. lip balm
  (Reason: Lip balm is used to protect lips.)

We must find a way to ________ similar problems in the future.

• Correct answer: C. avoid
  (Reason: "Avoid" means to prevent something from happening.)

Don’t drink too much milk, or ________ you will gain weight.

• Correct answer: B. but
  (Reason: "But" introduces a contrast between the actions.)

The doctor advised him to play more sports and ________ computer games.

• Correct answer: C. less
  (Reason: Less computer games, more sports for health.)

Who’s taking care ________ the children while you’re away?

• Correct answer: A. of
  (Reason: "Take care of" is the correct phrase.)

To ________ healthy you need between 1,600 and 2,500 calories.

• Correct answer: B. stay
  (Reason: "Stay healthy" is the correct phrase.)

You shouldn’t ________ spots when your hands are dirty.

• Correct answer: C. touch
  (Reason: "Touch" fits the context of dirty hands and spots.)

We shouldn’t spend much time ________ TV and ________ games.

• Correct answer: A. watching / D. playing
  (Reason: You "watch" TV and "play" games.)

My brother eats a lot of junk food, so he ________ on a lot of weight.

• Correct answer: D. puts
  (Reason: "Put on weight" means to gain weight.)

________ is one of the main reasons why the Japanese have long lives.

• Correct answer: C. Diet
  (Reason: A healthy diet contributes to a long life.)