Definition (情緒)
To suddenly look unhappy or disappointed.
面露失望之色
His face fell when he learned that he had missed the promotion.
當他得知自己錯過了升職機會時，他的臉沉了下來。
Her face visibly fell upon hearing the news.
聽到這個消息時，她的臉明顯沉了下來。
Their faces fell when they found out the vacation was canceled.
當他們發現假期被取消時，他們的臉都沉了下來。