1. The problem is to complete the square for the number 4. 2. Completing the square usually applies to quadratic expressions, but here we interpret it as expressing 4 as a perfect square. 3. Recall that a perfect square is a number that can be written as $a^2$ where $a$ is a real number. 4. Since $4 = 2^2$, it is already a perfect square. 5. Therefore, the completed square form of 4 is simply $4 = (2)^2$. This shows that 4 is a perfect square of 2.