* While
* As long as
* Meantime
* Meanwhile
Examples:
* Mientras estudias, puedo hacer la cena. (While you study, I can make dinner.)
* Mientras tengas el dinero, puedes comprarlo. (As long as you have the money, you can buy it.)
* Mientras esperamos, podemos tomar un café. (Meantime, we can have a coffee.)
* Mientras tú cocinas, yo pondré la mesa. (Meanwhile, I will set the table.)
The best translation will depend on the specific sentence and the meaning you want to convey.