9 . 阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。
Many people are afraid of flying in airplanes, but they shouldn’t be. Over time airplanes 1 (improve) their safety measures. Flying has become one of the safest ways to travel. In fact, when measured per mile, flying is 2 (actual) far safer than driving, or travelling by train.
Not only is flying the safest mode of transport, 3 it is also the fastest. Just a hundred years ago if you wanted to travel from China to the United States, you would have to travel by boat 4 many weeks. Fortunately now, you can get there in less than 24 hours. Airplanes are also quite 5 (comfort), and often offer in-flight entertainment, such as movies. This helps explain 6 travelling by plane is now the first choice for long 7 (distant) journeys.
Of course, that doesn’t stop some people from being afraid of flying. People can be frightened, 8 (think) about flying through the atmosphere (大气层) at hundreds of miles per hour. One of the main reasons that people are afraid to fly is that 9 (passenger) lack any control over the airplane, and have to place their trust in the hands of the pilots. Many people intend 10 (remain) in control.