In some states, revenues from the gasoline tax are used to build and maintain roads.

在一些州，汽油税的收入被用来修建和维护道路。

youdao

Only a handful of nations operate carriers, which are costly to build and maintain.

只有几个国家拥有航空母舰，其建造和维护费用极为昂贵。

youdao

As such, a system test environment is relatively inexpensive to build and maintain.

因此，系统测试环境的构建和维护相对便宜。

youdao

It is cheaper to develop air transport to remote, geologically unstable areas, than to build and maintain roads.

ECONOMIST: The Himalayas�� open skies

But who really has the time to build and maintain a complex and successful financial strategy on their own?

FORBES: DIY Investors: Don't Go It Alone

These chains then fold to form proteins, and it is the proteins that go on to build and maintain our bodies.

BBC: Tiny molecular machine apes cellular production line