相关单词近义词 unpopular 不流行的, thankless 不感谢的, unrewarding 无报酬的, unacknowledged 不被人承认的..., difficult 困难的, trying 难受的, ungratifying 忘恩负义的, unvalued 不受重视的, unsung 未被唱的临近词una, Unacid 返回 unappreciated