维持的英文：
keep
maintain
preserve

参考例句：

Sustain an institution
维持公共设施

The appeal court uphold the sentence.
上诉法庭维持了判决。

Sustaining food
维持体力的食物

There was too little food to support life.
食物太少，难以维持生命。

The heart performs a vital bodily function.
心脏起着维持生命的重要作用。

Keep the pressure up till you have blown the occlusion out.
维持压力直到把堵塞排除。

He has barely enough money to live on.
他的钱仅够勉强维持生计。

Food, clothing and shelter are needful for the maintenance of health.
衣、食、住是维持健康所必需的。

They could hardly make both ends meet and their debts were piling up.
他们简直没法维持生活，因而债台高筑。

George has to keep his nose to the grindstone to support his family.
乔治必须辛勤地工作以维持家庭生活

keep是什么意思：
v. 保持，处于；继续，重复；使耽搁；抚养；履行
n. 生活费，生活必需品

That news will keep.
那个消息留待以后再宣布。

They keep a shop.
他们经营一家商店。

How are you keeping?
你最近还好吧？

maintain是什么意思：
v. 保持，维持；支持，抚养；保养，维修；坚持

maintainable adj.
可维持的；主张的

motor maintainer
自动养路机

blade maintainer
单刃养路机

preserve是什么意思：
v. 保护；保存；维持；腌
n. 蜜饯；保护区；禁猎地

To make into a confection or preserve.
把…制成甜食或罐头

It did not canned or otherwise preserved.
它没有装罐或者用其他的方法保藏。

I preserved ginger in syrup.
我用糖浆腌制姜。