The new intern seemed insouciant about the deadline, which worried his project manager.

新來的實習生對截止期限似乎漫不經心，讓他的專案經理很擔心。

Despite the shipping delay, the supplier replied in an insouciant tone to our complaint.

儘管出貨延遲，供應商回覆我們的客訴時語氣卻很漫不經心。

Investors were alarmed by the CEO's insouciant remarks about the company's falling profits.

執行長對公司獲利下滑發表漫不經心的言論，令投資人感到震驚。