简单

simple; plain; brief; uncomplicated; straightforward; easy; elementary; undemanding; simply; plainly; simplicity; easiness; simplify; make simple; keep it simple; make it simple; tout court; easy as pie

礼貌

politeness; form; manners; manner; courtesy; civility; decorum; propriety; ceremony; polish; refinement; polite; courteous; decent; mannered; civil; well-mannered; genteel; decorous; respectful; graceful; gracious; politely; nicely; courteously

用语

use language; phrase; term; wording; expression; terminology; language; diction