when television first began to expand, very few of the people who had become famous as __71__ announcers were able to be equally effective __72__ . some of the difficulties they experienced when they were trying to __73__ themselves to the new medium were technical. when __74__ on radio, for example, they had become __75__ to seeing on behalf of the listener. this art of seeing for others __76__ that the announcer has to be very good __77__ talking. above all, he has to be able to __78__ a continuous sequence (序列) of visual (視覺的) images which add meaning __79__ the round the listener hears. in the __80__ of television, however, the announcer sees __81__ with the viewer. his duty, __82__, is completely different. he is there to make __83__ that the viewer does not __84__ any point of interest, to help him focus __85__ particular things, and to help him __86__ the images on the television screen. __87__ his radio colleague, he must know the __88__ of silence and how to use it at those __89__ when the pictures speak for __90__.

71. a) television b) advertisement c) radio d) newspaper

72. a) of b) in c) at d) on

73. a) adopt b) adjust c) alter d) adapt

74. a) working b) listening c) appearing d) showing

75. a) practiced b) experienced c) determined d) used

76. a) guarantees b) means c) convinces d) warns

77. a) at b) with c) in d) of

78. a) reflect b) create c) cause d) affect

79. a) to b) in c) on d) about

80. a) occasion b) matter c) example d) case

81. a) something b) everything c) nothing d) anything

82. a) moreover b) therefore c) furthermore d) nevertheless

83. a) clear b) definite c) sure d) easy

84. a) miss b) ignore c) drop d) catch

85. a) to b) at c) in d) on

86. a) reveal b) expose c) understand d) translate

87. a) unlike b) besides c) like d) as

88. a) price b) cost c) value d) worth

89. a) minutes b) periods c) times d) moments

90. a) them b) him c) themselves d) himself

答案：

71-75 cdbad 76-80 babad 81-85 bbcad 86-90 cacdc