大概三平方英里。

It's about three square miles.

Source: Tatoeba

Sentence Composition

1 大概 dàgài
  1. roughly
  2. probably
  3. rough
  4. approximate
  5. about
  6. general idea
=2 三 Sān surname San
=2 三 sān
  1. three
  2. 3
3 平方 píngfāng square (as in square foot, square mile, square root)
4 英里 yīnglǐ mile (unit of length equal to 1.609 km)