公司通过走后门的方式让不合格的产品获得了批准。

The company got their substandard product approved through a ___backdoor.

他们通过后门偷偷溜进了仓库。

They sneaked into the warehouse through a ___backdoor.

开发者意外留下了一个后门，导致系统安全性降低。

The developer accidentally left a ___backdoor in the system, compromising its security.