71.  Preston is particularly good at handling temperamental people.

72.  You have to be good at spotting trouble on the way and heading it off.

73.  He was very good at his work.

74.  She is very good at using her charm to get her way.

75.  Viruses tend to be good at surviving when a computer system crashes.

76.  Being very good at science subjects, I stood a good chance of gaining high grades.

77.  I bet you were good at games when you were at school.

78.  He was never good at communicating with the players.

79.  Mary was uncommonly good at tennis.

80.  She was good at repartee.