– Would you mind staying in such a noisy room?– No, but my son need a ______________ place to study in. 

Staying up late is _______ your health.

Now many people are________ in playing_______ games on the Internet.

My sister likes playing the guitar, but she can’t play ______.

---Now the air in our hometown is even       than it was before. ---So we must do something to stop it.