【简介】感谢网友“雕龙文库”参与投稿，这里小编给大家分享一些，方便大家学习。
in a complex society there are many jobs which must be done to keep the society running smoothly.
there must be many kinds of factory workers, salesmen, mechanics, policemen, firemen, miners, secretaries, bookkeepers, bus drivers and many other workers.
all these people are important to the comfort and safety of our everyday lives.
