副词是用来修饰动词、形容词、副词或整个句子的词汇。常见副词的用法如下：

1. 修饰动词：

例如：He sings beautifully. (修饰动词sings，描述方式)

　　　I always get up early in the morning. (修饰动词get up，描述频率)

2. 修饰形容词：

例如：She is extremely beautiful. (修饰形容词beautiful，描述程度)

　　　The lecture was unexpectedly boring. (修饰形容词boring，描述意外)

3. 修饰副词：

例如：She speaks English very fluently. (修饰副词fluently，描述程度)

　　　He runs quite slowly. (修饰副词slowly，描述程度)

4. 修饰整个句子：

例如：Interestingly, she always carries a book with her. (修饰整个句子，描述方式)

　　　Frankly speaking, I don't like him. (修饰整个句子，描述态度)