Tunnel engineering, as a professional technique, also has grown sound and mature.

隧道工程作为一门专业的工程技术，也已经健全和成熟起来。

youdao

Tunnel engineering, as a professional technique, also has grown sound and mature.

隧道工程作为一门专业的工程技术，也已经健全和成熟起来。

youdao