coarse: implies roughness, rudeness, crudeness, or insensitiveness of spirit, behavior, or language: found the ~ humor of her coworkers offensive.


vulgar: often implies boorishness or ill-breeding: a loud, ~ laugh.     （boorish粗糙：举止粗糙没文化不敏感不讨人喜欢，如your boorish behavior at the wedding reception你在婚礼接待会上的粗糙表现）


gross: stresses crude animal inclinations and lack of refinement: ~ eating habits make others lose their appetites.


obscene: stresses impropriety, indecency, or nasty obnoxiousness: ~ language that violated the broadcasters’ code.  nasty脏的dirty


ribald: applies to what is amusingly or picturesquely vulgar or indecent or crudely earthy: entertained the campers with ~ songs.  （earthy泥土的不文雅粗俗的，如an earthy sense of humour粗俗的幽默感）


coarse粗糙: 指言语行为精神等粗糙粗鲁原始迟钝，vulgar粗俗: 常表示行为粗糙教养差，gross粗鲁不雅臃肿;总的毛的:  强调动物的原始本性，不精致优雅，obscene下流: 强调举止不当下流肮脏可憎，ribald猥亵诙谐的: 既粗俗下流，又生动逗人


记忆方法: 1）首字母排列成VCROG，Very Contemptible ROGue让人轻视的无赖<==粗俗    rogue无赖流氓，如rogue state流氓国家


         2）粗俗的意思是有违品味道德mean offensive to good taste or moral principles.