这个密码锁需要输入三个零才能打开。

The combination lock requires you to enter three ___zeros to open it.

项目失败后，我们必须从零开始重建一切。

After the project failed, we had to rebuild everything from ___scratch.

每次使用前都要把电子秤归零。

Make sure to ___zero the digital scale before each use.

调查人员正在集中精力寻找线索。

The investigators are ___zeroing in on finding the clues.