perfect square number

例句：

1. 1. The perfect square of 4 is 16.
   4的完美平方是16。
2. 2. The square root of 25 is a perfect square.
   25的平方根是一个完美平方数。
3. 3.A perfect square has all sides that are equal to the length of the square.
   一个完美平方数的所有边长都等于该正方形的边长。