Lillith's formality and seriousness amused him.是什么意思？

Lillith's formality and seriousness amused him.

利莉思的拘礼和严肃让他觉得好笑。

formality

n. 礼节，拘谨，正式手续；

例句
The time had come to cross the great divide between formality and truth.
是时候跨越形式与真理之间的巨大分界线了。

and

conj. 和，与，而且，于是，然后，因此；

例句
I spend a lot on expensive jewelry and clothing...
我花很多钱购买昂贵的首饰和衣服。

seriousness

n. 认真，严肃地，严重地，非常严肃地；

例句
The Government has not yet grasped the seriousness of the crisis...
政府当局还没有意识到这场危机的严重性。

amused

adj. 被逗笑的，愉快的，顽皮的；v. “amuse”的过去式和过去分词；

例句
Sara was not amused by Franklin's teasing...
被富兰克林揶揄之后，萨拉的脸上全无笑意。

him

pron. (he的宾格)他；

例句
They said goodbye to him as he got aboard the train at Union Station.
当他在联合火车站登上火车之际，他们向他道别。