监牢

例句：

1. 1. The criminal was sentenced to life in prison.
   这名罪犯被判无期徒刑。
2. 2. The prisoner is serving his sentence in the cell block.
   这名囚犯正在服刑，在囚室中。
3. 3. He has been in prison for over a decade.
   他已经在监狱里待了十多年。