"你们是谁"可以用英语表达为 "Who are you"。以下是一些使用 "Who are you" 的例句：

1. Who are you and what is your purpose？

2. May I know who are you and what brings you here？

3. Excuse me, who are you and may I know your business？

希望这些例句对你有所帮助。