14)before/in front of用法区别:
表示"在……前"时,两者意义相近,in front of相对于空间位置而言,而before除表示位置关系之外,还可表示"面对","在……面前"等意。例如:
There,before/in front of the fisherman,stood a giant genie.
The Arab was finally brought before the judge.
A true man will never bow before any difficulty.
15)to/toward用法区别:
两个介词均可与go,come,walk,step,move等转移动词连用,to既表示运动方向,又包含运动的结果,toward只包含运动的过程。例如:A group of Italian soldiers led by a captain were advancing slowly toward the position of the enemy.The baby went to and threw himself into his mother.
16)as/for表示原因时的用法区别:
与famous,wellknown,popular搭配时,as表示"因……(身分)",for表示"因……(成就,特点,景观等)"。试比较:
Egypt is famous for the pyramids,while China,for the GREat Wall.
Zhou Enlai was worldfamous as an excellent diplomat(外交家).
17)at/on与work搭配表示"工作对象":
①at通常用于程序较单一的工作或事情名词前。而on多用于程序较复杂,过程较长的工作或事情名词前,即在表示下功夫的深度方面,要重于work at。
He's working hard at his lessons in order to pass the college entrance examination.
There are always many new problems for scientists to work on.
②work at中的对象只表明所从事的工作性质,而不说明在做什么,work on中的对象则是工作的具体对象。例如:
When the boy saw the soldiers,he stopped working on the branch.I'm now working at a new teaching plan.
