后备

I've got a security force as back-up.

我有一支保安队作为后备力量。

Clarkson suffered his injury playing in the reserves in midweek .

克拉克森在周中后备队比赛时受了伤。

In the paralic zone .there are ample oil and gas resources, moreover, it is the important mothball area and reliver of oil and gas industry to increase reserves and enhance output.

作为滩浅海的滨海,有丰富的资源,是目前业增储上产的重要后备区和接替区。