大人的英文：
adult
grownup

参考例句：

Jan was almost a grown-up.
简都快是个大人了。

The Boy walked with a manly stride.
那男孩走路迈着大人的步子。

I knew your lordship would not fail us.
我知道主教大人是不会让我们失望的。

"Him to whom your excellency pays that little annuity."
“就是大人给了他那一小笔养老金的那个人。”

“It’s not for me to contradict your Lordship’s Grace’s honour”said Cuddie
“大人在上，我怎么也不敢顶撞您呵！”卡狄说道。

brobdingnagian adj.
大人国的

Good morning,Your Grace!
大人,早上好!

Children should be seen and not heard
大人说话,小孩别插嘴

Small children sometimes manipulate grown-ups.
小孩有时能控制大人。

"Once a man, and twice a child"
当大人只有一次,当小孩却能两次

adult是什么意思：
adj. 成熟的；成年的
n. 成年的人或动物

These films are suitable for adults only.
这些电影只适宜成人观看。

Children unaccompanied by an adult will not be admitted.
儿童无成人带领不得入内.

The bear was a fully grown adult.
那只熊已完全发育成熟。

In the eyes of the law you are not an adult.
从法律的角度看你还没有成年。

Meeting adults embarrassed the shy child.
和家长见面使得这个害羞的孩子很尴尬。

grownup是什么意思：
n. 成年人
adj. 已长成的

Jan was almost a grown-up.
简都快是个大人了。

A grownup man can't change from short to tall in height.
一个成年人不能在身高上由矮变高。

Grown-ups often look back to the old days.
成年人常常回想过去的日子。

Tell children to tell a grown-up if they're being bullied.
告诉孩子们，如果被人欺负就告诉大人。

I have grown-up children who're doing well.
我的几个孩子已经长大成人并且事业有成。