against是什么意思？

　　例句：

　　1、the general feeling of the meeting was against the decision.

　　会议上普遍的意见是反对这个决定。

　　2、new information is matched against existing data in the computer.

　　新的资料和电脑中已有的'数据作了比较。

　　3、i don't want to go against your will.

　　我不想违背您的意愿。

　　4、teachers are up against some major problems these days.

　　老师们最近面临着一些重大问题。