Everybody who smokes knows it’s not good for you, and still 30 percent of Americans smoke -- 80 percent in some parts of the world. Why do people do it?
你知道，每个吸烟者都知道吸烟有害， 而仍有百分之30的美国人吸烟， 在世界上某些地区甚至高达百分之80。人们为什么明知故犯呢？