90.Their country is passing through__________(麻烦的) times.　

89. Her books enjoy a high p_________ among teenagers in many countries.

88.He tried to apply for the patent. But his a___________ was not accepted at all.

87.They realized there was some __________ (潜在的) danger behind the case.

86.Who can still have _________ (信任) in you despite your shortcomings?

85. The teacher did not explain its grammatical f_________.

84. Lightning usually a__________ thunder.

83．They considered themselves to be s_________to black people.

82.Having made good preparations, the students all made very wonderful ____________(陈述).

81. University professors often ___________ (抱怨) that students are handing in papers using false information they found on the Internet.