英语语法分析

You should make a copy of the disk as a backup.

你应该将磁盘复制一个备份。

《牛津词典》

If that happens, the grasshopper has a backup defense.

如果发生这种情况，蚱蜢就有了后备防御。

In areas where the wind dies down, backup electricity from a utility company or from an energy storage system becomes necessary.

在风能不稳定的一些地区，需要供电事业公司或者能量储存系统来提供备用电能。