Wear（one's）heart on（one's）sleeve的意思是流露感情；喜怒形於色。例如：It's obvious how Gary feels about Paula；he wears his heart on his sleeve.加裡對保拉的感情非常明顯，他毫不掩飾他的感受。
wear heart on sleeve這個用語最有可能的起源與幾世紀之前的比武有關，這種比武稱為joust（長槍競技），即騎士在馬上以長槍比武，只要以長槍將對方打落下馬就贏了。據說在比武期間，騎士會攜帶其愛人贈送的有色彩的信物，也許是在手臂上綁著手帕。首先使用這個說法的人就是莎士比亞，出自17世紀初的《奧塞羅》。
看看老外聊天時怎麼用wear heart on sleeve：
Mitch:I'm really upset about Gloria.
對于格洛麗亞的事我真的很沮喪。
Sally:Try not to think about it.You'll get over her.
別再去想了，你會忘了她的。
Mitch:I just can't stop thinking about her.
我就是忘不了她。
Sally：You shouldn't wear your heart on your sleeve SO much.
你應該稍微控制一下你的情感。
wear heart on sleeve例句精選：
She's a shy person. She's never been one to wear her heart on her sleeve.
她是個害羞的人，從來不敢把心裡的真實想法表達出來。
Your friend may, however, warn you "not to wear your heart on your sleeve."
然而你的朋友可能提醒你，「不要太情緒化。」
Of course I care, Alan. It's just, I don't wear my heart on my sleeve.
當然，我當然關心啦，只是我不擅於言表而已！
He did not wear his heart on his sleeve, and when he left his chambers to walk to that last meeting, his face was much as usual.
他並不感情外露，當他離開辦公室去參加最後一次會議時，他的臉色跟平常一樣。