We kept up a correspondence for many years.
我们保持了很多年的通信联系。
Have you kept in contact with any of your friends from college?
你和你大学里的朋友还保持联系吗？
Your application will be kept on file.
你的申请书将存档。
The thought kept going round and round in her head.
这个想法一直萦绕在她的心头。
He kept us at it all day.
他让我们不停地干了一天。