Like water off a duck's back

and did not seem to mind it in the least.

不过，对此他满不在乎。

He doesn't give a hoot whom he bawls out.

不管骂谁他都满不在乎。

with an assumption of indifference

装着满不在乎的样子

He sits down again carelessly.

他又满不在乎地坐下来。

put a bold/good face on sth.

1. 对某事装作满不在乎

You look as if you didn't care.

你看上去好像满不在乎。

display a cavalier attitude towards the feelings of others

对别人的感情满不在乎

with an uninterested look,

一脸满不在乎似的，

He makes nothing of walking ten miles.

他走十哩路满不在乎。

in an unconcerned manner

满不在乎地,以漠不关心的态度

She only stood, straight and fine.

她只是站着一动也不动，满不在乎。

I just went to eat by myself.I could have cared less that you weren't coming.

我一个人去了，你们不来，我满不在乎。

Mr. Carton's manner was so careless as to be almost insolent.

卡尔顿先生一副满不在乎的神气，几乎有点无礼。

She doesn't mind splashing her money about.

她满不在乎地大手大脚花钱。

He didn't care a fig for his mistake.

他对所犯的错误满不在乎。

As they had ample traveling funds, it didn't matter if they stayed on a few days longer.

身边旅费充足，多住几天，满不在乎。

He gives the impression of not caring a damn.

他给人的印象是满不在乎.

Act as if you didn't care."

拿出一副满不在乎的劲儿来演戏。”