too big for one's boots自大這個習語當中的boots也可以用britches（馬褲）代替，都是用來比喻一個人過度自我膨脹，最後連靴子或馬褲都塞不下。要注意big用來表示抽象的意思時，除了可以當「浮誇」解釋，還有「心胸寬大」的意思。
看看老外聊天時怎麼用too big for one's boots:
Roy: I think the new girl has a crush on me.
Tina: No, she doesn't. You' re too big for your boots Roy: She told me I'm the most dependable guy she knows.
Tina: I think she just wants people to like her.
Roy: I don't believe you. I'm going to ask her out.
羅伊：我覺得那個新來的女生對我有意。
蒂娜：才沒有呢，你太自大了。羅伊：她跟我說，我是她見過最可靠的人。
蒂娜：我覺得她只是想要讓大家喜歡她而已。
羅伊：我才不信，我去約她。
too big for one's boots例句精選：
He thought too much of himself and was getting too big for his boots, though he kept his thoughts to himself.
他少年得志，目中無人，不過沒有表露出來。
Haas was a top student in his class, but now he is too big for his boots.
哈斯在班上是最好的學生，但現在他太目中無人了。
Your son has grown too big for his boots, you'd better put in his place.
你兒子變得太傲慢了，你最好讓他有自知之明。
This provoked a furious row, and Cuming accused me of becoming too big for my boots.
這一點引起了激烈的爭吵。卡明指責我狂妄自大。
拓展學習：
arrogant 傲慢的
cocky 太過自信的；驕傲的
self-abased 自卑的
be puffed up自負的
on an ego trip 自吹自擂
have a big heart 寬宏大量