We kept up a correspondence for many years.

　　我們保持了很多年的通信聯系。

　　Have you kept in contact with any of your friends from college?

　　你和你大學里的朋友還保持聯系嗎？

　　Your application will be kept on file.

　　你的申請書將存檔。

　　The thought kept going round and round in her head.

　　這個想法一直縈繞在她的心頭。

　　He kept us at it all day.

　　他讓我們不停地干了一天。