问题
单项选择题
Mary did her homework ______, so she left school early.
[A] slow [B] happy [C] quickly
答案
参考答案：C
解析： 考查副词。slow“慢的”，形容词；happy“高兴的，形容词”；quickly“快地，迅速地”，副词。而且根据后边的句意也应该确定选C。[知识拓展] 应该用副词修饰动词，形容词修饰名词用。如：She is a very beautiful girl．