Many people use E-mail,blogs,text messages and social Web sites like Facebook to keep in touch with their friends.

VOA: special.2009.02.06

and it's a really convenient way to keep in touch with them.

这样联系他们真的很方便。

用社交网站找到的人 - SpeakingMax英语口语达人

And he promises that he'll keep in touch.

他答应会跟你保持联系。

I'm worried 课堂 - SpeakingMax英语口语达人