sq.m.

例句：

1. 1. The city is about 20 square miles in size.
   这个城市大约有20平方英里那么大。
2. 2.He moved to a new apartment that was 5 square miles away.
   他搬到了一个离新公寓5平方英里远的地方。
3. 3.The park covers an area of approximately 10 square miles.
   这个公园的面积大约是10平方英里。