It seems like everywhere a person goes there is at least one person with a cell phone to his ear. Even in places where cell phone usage is banned such as concert halls or movie theatres there is the 66 offender, or at least a few people using the text messaging feature on their phones.
Cell phone usage has exploded over the past decade and continues to rise. Nearly 200 million people in the United States have cell phones and there are 67 over one billion users worldwide. That means there are a lot of phones 68 their frequencies over the airwaves at any given time.
Concern has arisen over whether or not cell phone usage can harm a person’s health. Brain cancer rates in the United States have risen since cell phones were 69 , leading some people to wonder if cell phone usage is the reason for the 70 .
Some people say the biggest danger with cell phones isn’t from the either real or perceived potential to develop cancer, but from 71 while using the cell phone. How many of us have seen vehicles driving quite erratically（不稳定地）down the road. And we often see when we get near the vehicle the driver on a cell phone is 72 on a cell phone. It is a proven fact that a driver on a cell phone is 73 attentive and more likely to get in an accident. And, hands-free sets aren’t the answer that some people may believe. Yes, they 74 both hands for driving and prevent a person from getting a sore arm, 75 the driver’s mind is still 76 the conversation and therefore less attentive to what is 77 around him or her on the road.
66. A. busy B. always C. occasional D. occasionally
67. A. well B. good C. better D. best
68. A. delivering B. carrying C. taking D. sending
69. A. allowed B. invented C. introduced D. bought
70. A. increase B. decline C. improvement D. rose
71. A. attention B. attractive C. careless D. inattentiveness
72. A. using B. talking C. moving D. handing
73. A. more B. less C. least D. fewer
74. A. hold up B. pick up C. put up D. free up
75. A. therefore B. as C. but D. though
76. A. taken up B. filled by C. occupied with D. picked up
77. A. happening to B. going on C. talking about D. moving about