1. 程度副词的用法特点
程度副词用于表示程度，常见的程度副词有 fairly, pretty, rather, quite, very, much, too, greatly, highly, awfully, deeply, partly, perfectly, really 等；程度副词主要用于修饰形容词和副词，有的还可修饰比较级(如much, rather 等)和最高级(如quite, much, almost 等)。如：
I'm quite certain of that. 对那事我完全可以肯定。
He speaks very highly of you. 他对你评价很高。
His illness is far more serious than we thought. 他的病比我们想像的要严重得多。
注：quite 有时也修饰比较级，但只用于quite better(身体康复)这一表达。有的程度副词(如quite, rather, almost等)可修饰动词，但有的(如fairly, pretty, very等)则不能修饰动词。
2. 频度副词的用法特点
频度副词表示动作发生的次数，常见的频度副词有ever, never, rarely, seldom, once, often, occasionally, constantly, frequently, usually, continually, always 等。频度副词通常位于实意动词之前，动词be、助动词、情态动词之后(有时为了强调，频度副词也可位它们之前)。如：
The children are seldom ill. 这些孩子很少生病。
Do you often watch television? 你常看电视吗？
I've never been out this late before. 我从来没在外面待到这么晚。
注：有的频度副词可位于句末(尤其受very, only修饰时)。如：
I go there alone very seldom. 我很少一个人去那儿。
You should oil that machine often. 你应当经常给那台机器上油。
注：含有否定意义的频度副词置于句首时，其后要用倒装语序：
Never have I read such books. 我从未读过那样的书。
