81.There ought to be less anxiety over the perceived risk of getting cancerthan ___ in the　public mind today.
A) exists
B) exist
C) existing
D) existed

82. The professor can hardly find sufficient grounds _____ his argument in favor of the new theory.
A) which to base on
B) on which to base
C) to base on which
D) which to be based on

83. ________ can help but be fascinated by the world into which he is taken by the science fiction.
A) Everybody
B) Anybody
C) Somebody
D) Nobody

84. How many of us ___, say, a meeting that is irrelevant to us would be interested in the discussion?
A) attended
B) Attending
C) to attend
D) have attended

85. Hydrogen is the fundamental element of the universe ____ it provides the building blocks from which the other elements are produced.
A) so that
B) but that
C) in that
D) provided that

81.D 82.A83.B84.D85.B