They know me—I'm a regular customer.

我是老主顾，他们都认识我。

Sure, you are regular customer.

当然，您是老客户嘛！

And I'm a regular customer here.

我是你们这的常客了。

Is he your regular customer?

他是你们的老主顾吗？

John's our regular customer.

约翰是我店的常客。