听闻很多童鞋，为了过英语四级，背了单词，记了语法，可就是很快忘记了，所以楼主决定，推出每日一练，帮助大家在特定的语境中记住单词，掌握语法，轻松过四级。
今日份题目
英语四级—单选(2007.12)
One factor that can influence consumers is their mood state. Mood may be defined a temporary and mild positive or negative feeling .
A) must have lasted
B) will have lasted
C) would last
D) has lasted
答案：A
此题be defined as 属于固定搭配短语，故选A。此题翻译为：影响消费者的一 个因素是他们的情绪状态，暂时的和温和的积极或消极的感觉。
