french leave表示不辞而别，悄悄离去；擅离职守。是讽刺过去法国人随意离席的行为。

【例句】
He took French leave during the dinner party.
晚餐聚会时他不辞而别。

Why did you take French leave yesterday?
昨天怎么没打招呼就离开办公室啊？