4. Now, It is commonly / generally / widely believed / thought / held / accepted / felt / recognized / acknowledged that....

They claim / believe / argue that ....

But I wonder / doubt whether ...

4.1 It is commonly believed that the rise in teenage smoking is the inevitable result of economic development. They argue that if there are no cigarette advertisement on TV, no cigarettes available everywhere, and no adequate pocket money, teenagers are unlikely to take up the habit of smoking. But I doubt that it is a satisfactory explanation. While conceding the effect of advertising and other commercial factors, I think that the primary cause is social and individual rather than economic.

人们普遍认为青少年吸烟人数上升是经济发展不可避免的结果。他们认为：如果电视上没有香烟广告，香烟不是到处可买得到，孩子的零用钱不是很多的话，青少年不太可能染上吸烟的习惯。但我怀疑这是否是一个满意的解释。虽然有广告和其它商业因素的影响，我认为主要原因是社会和个人因素而不是经济上的。

4.2 It is widely felt that there is a fear plainly uppermost in the minds of most people today. They are afraid of the future, and if you ask them why, they conveniently blame the atomic bomb. But I suspect that the nuclear weapon is only the scapegoat for our fears. We are not afraid of the future because of a bomb. We are afraid of bombs because we have no faith in the future. I believe people no longer have faith in our ability to control our own future.

人们普遍感到现在大多数人明显地有一种恐惧感。他们怕将来。如果问他们为什么怕，他们会很随意地怪原子弹。但我怀疑，核武器不过是我们害怕的替罪羊。我们怕将来不是因为有了原子弹，说我们怕原子禅，实际上是对未来没有信心。我认为人们对自己是否有能力控制将来已丧失信心了。