In ancient times, people's only transportation means（方式）was their feet. So it was difficult for them to travel from one place to another. As a result, they knew few things about the outside world. The world was too big for them to understand.
With the development of modern science and technology(技术), more and more transportation means appear: bicycle, bus, car, train, ship, plane, etc. They carry goods and passengers to every corner of the world. And they shorten(缩短) the distance(距离) between people. With the help of these modern facilities (设备），people all over the world can stay in touch with each other.
So it's easier for people from different nations to understand each other and to communicate with each other. Thus, this world is getting smaller and smaller, just like one big family.
