副词在句子中的位置以及作用：
作状语：
① 时间副词：一般放在句首或句尾,注意,early、late、before、later、yet等一般放在句尾,already、just一般放在动词的前面。如：We will visit the Great Wall tomorrow. / They have already been to the UK twice. / Soon the lost boy found his way back home.
② 频度副词：一般放在be动词之后或者助动词与主要动词之间,但sometimes、often等还可以放在句首或句尾,usually可放在句首,once可放在句尾,twice、three times等一般放在句尾。如：Sometimes I get up early./ The workers usually have lunch at the factory. / Take this medicine twice a day.
③ 方式副词：一般放在行为动之后,suddenly可以放在句首、句尾或动词之前。如：Old people can hardly walk as quickly as young people. / Suddenly he saw a light in the dark cave.
④ 地点副词：一般放在句尾,但here、there还可放在句首。如：There you can see thousands of bikes running in all directions. / The frightened wolf ran away./ He walked out quietly and turned back soon.
⑤ 程度副词：修饰动词时,放在动词之前;修饰形容词或副词时,放在形容词或副词之前。但注意,enough总是放在被修饰的形容词或动词的后面;only位置比较灵活,总是放在被修饰的词的前面。如：I nearly forgot all about it if he did not tell me again. / It was so strange that I could hardly believe my ears. / She got to the station early enough to catch the first bus.
⑥ 疑问副词：用于对句子的状语进行提问,位置总是在句首。如：When and where were you born?/ Why did little Edison sit on some eggs?/ How do you do?