be on guard英语标准发音:be on guard英式发音:美式发音:翻译中文当心be on guard - 基本释义[词典1]保持警惕be on guard - WEB词典be on guard警惕防备防范戒备be strictly on guard against小心警惕地防范严防Be on your guard发现敌人了你们应当谨慎你们务要儆醒 参考资料: 1.百度翻译:be on guard2.有道词典:be on guard3.爱词霸:be on guard