小姨子的英文：
wife's younger sister

wife是什么意思：
n. 已婚女子，妻子

Ann was cast as the wife.
安妮被选派扮演妻子的角色。

My wife was there among others.
我妻子和其他一些人在那儿。

The wife is the key of the house
妻子是家庭的关键

younger是什么意思：
[ young ]的形容词比较级

The girl in red is his younger sister.
那个穿红衣服的女孩是他妹妹。

Anne's not getting any younger.
安妮一点没有变年轻。

The younger mechanic readily fixed the car.
年轻的机修工很快地把车修好了。

sister是什么意思：
n. 姐妹；修女；护士
v. 姐妹般对待
adj. 姐妹般的；同类型的

The elder sister is called Mary.
姐姐名叫玛丽。

It is unnatural for sisters to be at variance.
姐妹之间不和是不近人情的。

The girl in red is his younger sister.
那个穿红衣服的女孩是他妹妹。