It is important for some classes to have exactly one instance.

重要的是，一些班级有精确的一个实例。

youdao

Therefore, our helper classes wait some time for the directory queries to complete.

因此，帮助器类会等待一段时间以完成目录查询。

youdao

Therefore, our helper classes wait some time for the directory queries to complete.

因此，帮助器类会等待一段时间以完成目录查询。

youdao