有一读者问： 新英语课本每到期中、期末的单元总有一标题：Mainly Revision。mainly是副词，怎能用以修饰名词revision呢？
英语中有一些副词，如mainly, chiefly, especially, only, merely, even等，具有突显词语的作用，其后可接各种词语，包括名词在内。有的语法家称之为“焦点副词”。再以mainly为例：
(1)There I saw a lot of people, mainly women and children. （mainly后接名词）
(2)The union soon formed twenty branches, mainly in London. （mainly后接介词短语）
(3)They argued that the tax will mainly benefit the rich. （mainly后接动词）
