All theories originate from practice.

所有的理论都是源于实践。

youdao

All theories originate from practice and in turn serve practice.

所有的理论都来源于实践，并反过来为实践服务。

youdao

All theories originate from practice and in turn serve practice.

任何理论都来源于实践，反过来为实践服务。

youdao

All theories originate from practice and in turn serve practice.

任何理论都来源于实践，反过来为实践服务。

youdao