63. There is a s _____ problem . You must be more careful.

62. I w _____ the reason for his being late.

61. Don’t you want to go to c _____ when you finish middle school?

60. I received an i ______ yesterday, of course I accepted it.

59. Xiao Ning is the o _____ of the conference.

58. The s _______ expression on his face suggested that maybe something important had

　 happened to him.

57. The teacher asked me to pay special a _____ to my spelling.

56. The m _____ team is made up of 8 doctors and 9 nurses