How long has Mr. Green lived Lanzhou?-He’s lived here five years.[ ]

Do you know _________ an “o” and _________ “u” in the word “computer”?

I want to buy a hat, but there are so many kinds that I can’t decide to take.

He is so _________ when he hears the __________news.

Jack likes playing ______ chess, but he doesn’t like playing_______piano.