1. to broaden
They're preparing a project to broaden the bridge.
English word "扩大"(to broaden) occurs in sets:词汇 (A-D) - Vocabulary (A-D)
2. to expand
to expand the horizont
We are planning to expand our business.
English word "扩大"(to expand) occurs in sets:词汇 (E-H) - Vocabulary (E-H)