Some people think bicycles have changed people's lives; some people think automobiles have changed people's lives. Personally, I think that airplanes have changed people's lives. There are many reasons why I hold this opinion, and I will explain two important ones due to this limited time. First, airplanes realized human biggest dream, which is flying in the sky. Second, all people of the world can largely reduce the time of travel by airplanes.
One important reason is that airplanes realized human biggest dream that human beings can freely fly in the sky. Long time ago, people want to fly, but they could not until the early last century. Since airplanes were invented, it became possible that people challenge and conquer space. Now, people can not only fly in the sky, but also fly out of earth. Furthermore, with the development of science and technology, people will freely travel in out space one day.
Another important reason is that airplanes' speed is so fast that people can largely reduce a lot of time of travel. For example, it takes about 12 hours to travel from America to China by airplanes. However, if people choose to ship, it will take several months. Obviously, the time that people travel by airplanes is far less than that of traveling by ship. As a result, people who come from different countries can easily come together to do their common businesses by airplanes, such as discussing environmental issues of the world.
Of course, other transportation vehicles have also some advantage. However, from what I have discussed above, we can easily draw a conclusion that airplanes not only are important vehicles, but also have changed people's lives in large extent. I believe people will go to other planets by spaceship in future.