be doing time at

例句：

1. 1. He's been in prison for five years now.
   他已经服刑五年了。
2. 2.She's serving her sentence in a local jail.
   她在一所当地的监狱服刑。
3. 3. The man is under sentence for his crime.
   这名男子因他的罪行被判刑。