against主要用作介词，意为“反对，违反；对……不利；紧靠，倚，碰撞；针对；预防，抵御；（体育比赛）对阵；以……为背景；参照，和……相比；（赌博）预计……的失败”等。
against的用法有哪些
1.against作“反对”解时反义词是for。
2.against用在fight，strive，struggle等词后面，同with意思相同，不过against更强调一种困难中的反抗。
We fight for the weak against the strong.
3.作为介词，against后接的宾语有时可省略。
We have saved some money against our old age.
我们存了一些钱，以备老年之用。
Our defences must be reinforced against attack.
我们必须加强防御设施以抵御进攻。
His eloquence did not avail against the facts.
他的雄辩在事实面前不起什么作用。
against例句
He came out against the plan. 他公开表示反对这个计划。
She leaned against the wall. 她倚靠着墙。
He's dead against the idea. 他坚决反对这个想法。
Lilacs grew against the side wall. 丁香树倚着边墙生长。
The charges against her are baseless. 针对她的控告毫无根据。
The report argues against tax increases. 该报告陈述理由反对增税。
The peasants arose against their masters. 农民奋起反对奴役他们的人。
Rain drove against the window. 雨打着窗户。
It isn't insured against theft. 它没有买盗窃险。
Are we insured against theft? 我们保了盗窃险没有?
The evidence is against him. 证据对他不利。
Murder is a crime against nature. 谋杀是一种有违天性的罪行。
He warned us against pickpockets. 他提醒我们要提防小偷。
Rain pattered against the window. 雨点啪哒啪哒地敲击着窗子。
I was vaccinated against tetanus. 我接种了破伤风疫苗。
What were the odds against? 赔率是多少?
She cuddled up against him. 她依偎着他。