back up each other

基本解释

At the same time, data can be stored in the built-in hard drive or external disk U, to back up each other to ensure the safety of the data;
数据可同时存储在内置硬盘或外接 U盘上，互为备份确保了数据的安全；
blog.china.alibaba.com
The defenders of the consensus tend to stress the general consilience of their efforts—the way that data, theory and modelling back each other up.
护卫整体共识的人倾向于强调他们研究的一致性--也就是数据、理论、和模式能相互提供证明。
On the other hand, through the network, the hosts can back up each other, if a host fails, it may be the task of the network host, took the other to complete.
另一方面，通过网络，各台主机可以彼此互为备份，如果某台主机出现故障，它的任务可由网络中其它主机代为完成。

Back home, they hooked up their cheap computers and hard drives to each other to form a sort of homemade parallel processing system.
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The lakes have filled back up, the plant life is so green it's dazzling to behold, and neighbors are boasting to each other across the fence how low their water bills are.
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