If indeed silence is golden, it is also becoming as rare as gold. It seems that the progresses of man includes a rising volume of noise. 71. ______ In every home a stereo or television will fill the rooms sound, between 72. ______ sunrise and sunset, streets and highways are a constant source of voice from cars, buses, and trucks. You can pass any factory or 73. ______ construction area and the roar of their machinery will make your ears 74. _______ ringing. Music is played in every supermarket, most restaurants, and 75. _______ many offices, big cities of the world are well-known by their noisiness. 76. _______
Noise pollution is the new side effect of our technological age. Day or night, the sound of the work fills the air. It seems 77. _______ that the smoothing effects of to be found. Even the quiet of our careful protected wilderness areas can be 78. _______ invaded at any moment by a passed jet. 79. _______
We are learning, finally, that silence is a natural resource and must be protected by law. It appears that we all find company in sound, if we all demand a little quiet from time to time. 80. ________
71. progresses, progress 72. (room), (room) with 73. voice, sound(s)/noise(s) 74. their, its/the 75. ringing, ring 76. by, for 77. the (work), / (work) 78. careful, carefully 79. passed, passing 80. if, but/but/yet/though/although
to be found. 
