我们通过电子邮件保持联系已经很多年了。

We've ___kept ___in ___touch by email for many years.

请和我保持联系。

Please ___keep ___in ___touch with me.

尽管我们现在住在不同的城市，但我们仍然保持联系。

Even though we live in different cities now, we still ___keep ___in ___touch.