beck and call
随传随到；即刻可用
口语·描述被呼来喝去或随叫随到
英文释义
to be at someone's immediate service or disposal; to be ready to obey someone's command or request at any time
例句
She expects her assistant to be at her beck and call 24/7.
典故来源
源自中世纪英语，'beck'指点头或手势命令，'call'指口头召唤，强调随时服从。