It's just an operator, a language construct.

这只是一个操作员，一个语言结构。

youdao

Here, an operator communicates with a caller using sign language and a video connection.

图中显示一工作人员与呼叫者视频连线用手语交流。

youdao

Here, an operator communicates with a caller using sign language and a video connection.

图中显示一工作人员与呼叫者视频连线用手语交流。

youdao