当家的英文：
manage household affairs

参考例句：

The foot on the cradle,the hand on the distaff,a sign of good housewife.
脚踩摇篮手纺纱，一定是个好当家。

It's obvious that it is your wife who wears the pants I your family
看得出来,在你们家是你老婆当家

Who's(the)boss in this house? ie Is the wife or the husband in control?
谁是一家之主(是妻子还是丈夫当家)

manage是什么意思：
v. 经营，管理；处理，解决；设法

An assistant manager is inferior to a manager.
经理助理的地位比经理低。

To manage;contrive.
试图；设法做到

They managed this trick.
他们完成了这个绝招。

household是什么意思：
adj. 家喻户晓的；日常的，家常的；王室的；家庭的
n. 家庭；家务

He is a household legendary figure.
他是个家喻户晓的传奇性人物。

Computers have become household toys.
计算机已成了家庭的消遣玩意儿。

He was sent to superintend a household staff.
他被派去管理佣人。

affairs是什么意思：
n. 事务；事件；风流韵事

You have to investigate into this affair.
你必须调查研究这件事。

The affair had a strange sequel.
这一事件的结局很奇怪。

A committee was constituted to investigate into that affair.
建立了一个委员会以调查那件事。