Definition
A minor issue or annoyance that spoils something that would otherwise be positive or pleasant.
美中不足之處；令人掃興的人或事物。
The project was progressing smoothly, with the only fly in the ointment being that the budget had been exceeded slightly.
項目進展順利，唯一的美中不足是預算稍微超支了。
The hotel was perfect, the only fly in the ointment being the slow internet speed.
酒店很完美，唯一的美中不足是網速很慢。
The wedding was wonderful, but the only fly in the ointment was the bride’s slightly ill-fitting dress.
婚禮非常美好，唯一的美中不足是新娘的禮服稍微有點不合身。