a fly in the ointment 指美中不足。比如:
- Rachel seems to be the one fly in the ointment of Caroline's smooth life.
蕾切尔似乎是卡罗琳一帆风顺的生活中唯一的麻烦。
这一表达出自《钦定版圣经》中《传道书》(Ecclesiastes)第10章第1节:
- Dead flies cause the ointment of the apothecary to send forth a stinking savour.
死苍蝇使作香的膏油发出臭气。