against是什么意思？

　　例句：

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

　　會(huì)議上普遍的意見是反對(duì)這個(gè)決定。

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

　　新的資料和電腦中已有的數(shù)據(jù)作了比較。

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

　　我不想違背您的意愿。

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

　　老師們最近面臨著一些重大問題。