III) 

68, Think→ thought

69, A → an

70, To tell → telling

71, Spending → spent

72, Entertain → entertaining

73, So → Therefore

74, On → for

75, Who → whose

76, Become → are

77, Was → ∅

78, Should → shouldn't

79, Too → so

80, But → and

IV)

81, The television has been switched off because it was making a lot of noise.

82, He is capable of understanding the most difficult part of the lesson.

83, She told me that I should select another programme.

84, Fax machine is used to send and receive letters and pictures quickly.

85, This is the biggest building for the homeless.

86, Unless you see the game show, your father will be able to see his favorite play. 

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