-（基本的;主要的）root;radical;basic;fundamental;essential;cardinal;foundation;origin:
fundamentalinterests;根本利益
basicreason;rootcause;根本原因
-（全然）utterly;completely;entirely;atall:
Hedoesn'tknowFrenchatall.他根本不懂法文。
-（彻底）radically;thoroughly:
Theproblemhasbeencompletelysolved.问题已根本解决。