66．Are you ____ trouble, Jim?

65．The students walked ____ the gates with Uncle Wang.

64．What have you done ____ the milk?

63．I'm sorry．I won't talk to others in class ____ now on.

62．If you break the window, you'll have to pay ____ it.

61．Have you heard ____ Jim yet?

60．Someone is knocking ____ the door.

59．My teacher was angry ____ me.

58．He didn't go ____ bed until twelve o'clock.

57．Don't play ____ fire．It's dangerous.