a cool head的用法和樣例：
例句
- It's a distinct advantage around here to keep a cool head when things begin to go wrong.
事情開始出差錯時，保持清醒的頭腦是這裡的一個顯著的優點。 - He has a cool head at all times.
他不論什麼時候都有清醒的頭腦。 - Keep a cool head when thing go wrong.
出問題時要保持冷靜的頭腦。 - The occasion calls for a cool head.
在這樣情況下需要有冷靜的頭腦。
