曾经有一幅漫画，画面上：高楼林立的大都市里，一条长龙似的队伍等在一栋建筑外面，其中一个人间排在前面的人：“排队干什么？”回答曰：“排队看树。”──这可能是画家过于夸张了，但随着现代化大工业的进一步发展，人们对地球的开发进一步加速，城市化的加大，而使得久居? Once upon a time, there was a comic on the screen: in a tall metropolis with many tall buildings, a long queue of people waited outside a building. One of the top people in the world was: “What are you waiting in line?” Replied: “Stand in line and watch the tree.” ─ ─ This may be too exaggerated painter, but with the further development of modern large-scale industry, people further accelerate the development of the Earth, urbanization, which makes a long time?