第一， 情景對話

A: Bob, can you tell me how many students passed the college entrance examination this year?

鮑伯，你能告訴我今年有多少人考上大學了嗎？

B: Off the top of my head, I'm afraid I don't know.

不查的話，我也搞不明白。

A: Never mind. Well, can you tell me where I can get the information?

不要緊，你知道從哪里能查到有關的信息嗎？

B: Maybe from the Education Daily.

《教育報》上也許會有。

第二， 詞海拾貝

off the top of one’s head

exp. From memory or without much or careful consideration. （不假思索地，信口開河地）

e.g. She answered the teacher's question off the top of her head.

她隨口回答了老師的問題。

e.g. John can list the capital cities of all 50 states off the top of his head.

約翰能不假思索地列出所有50個州的首府城市。

e.g. Mary: How much do you think this car would be worth on a trade?

你認為這輛車在市場上買多少錢？

Fred: Well, right off the top of my head, I'd say about a thousand.

嗯，不看汽車行情資料的話，我覺得大概一千元。