一、用来指人
every man Jack, every Jack one 每个人、人人
Jack of all trades and master of none 万事皆通而一无所长的人
a Jack on both sides 模棱两可，两面派
Jack at a pinch 临时拉来帮忙的`人
All work and no play makes Jack a dull boy. 谚语：只工作不玩，聪明的孩子也会变傻。
All shall be well, Jack shall have Jill. 谚：有情人终成着属。
Jack among the maids 讨好女人的男子
Jack would be a gentleman if he had money. 谚语：低微的人有钱也会成为绅士。
Jack is as good as his master. 谚：伙计不比老板差，卑贱者未必不如高贵者。
Jack in the water 码头打杂工
cheep Jack 卖廉价货物的小贩
a Jack in office 自命不凡的小官吏，官僚
Jack the lad (青少年帮派中的)头号人物
二、指物
Yellow Jack 医学上的“黄热病”
Jacks are common to all that will play.
谚语：乐器对于所有想要弹奏的人都一样。Jacks是古时类似钢琴的弹奏乐器。
a Jack of straw 稻草人
to make one's Jack 赚很多钱
学识谷
