Fortunately, however, ancient men made tools of stone, especially flint,

然而， 幸运的是，远古人用石头制作了工具，特别是用燧石，

Once we get down to the oil, it usually flows to the surface because great pressure,

一旦到达油层，石油就会由于地下巨大的压力流到地面上来，

and it is only in the seas and rivers, and sometimes lakes, where mud and sit have been continuously deposited,

所以只有在泥沙不停淤积的海洋和江河里，有时在湖泊里，

Then the cannons of the anchored warships thundered a salute to which the Vasa fired in reply.

这时，停泊在港口的其他战船向瓦萨号鸣炮致礼，瓦萨号也鸣炮回礼。

or ignorant, or even that he has been unfair or unjust.

甚至承认自己做得不公平或不公正的父母，

and whom I respect, confess at once that they have little idea where they are going when they first set pen to paper.

和尊敬的作家，都立即承认在他们动笔时，不清楚要写什么，怎么写。