31.   My knees were knocking and my lips quivering, making it difficult to get round the words.

32.   She writes long sentences without verbs, as if the rocky terrain inevitably makes action difficult.

33.   Some employers have made life difficult for employees who need time off for extended illnesses.

34.   Some of the groups found that the sound quality was so poor as to make it difficult to listen to the recordings.

35.   Staffing problems made it difficult to maintain the quality of the service.

36.   The audacity that makes her so powerful on the court makes her difficult off it.

37.   The caterpillars can be picked off, but their coloring makes them difficult to see, especially when they are small.

38.   The confusions of war, the tight security covering the country, made communication difficult.