#### Answer

real number
complex number;

#### Work Step by Step

$-4$ is known to be a real number.
RECALL:
The number $a+bi$ where $a$ and $b$ are real numbers is a complex number.
Since $-4= -4 + 0i$ and $-4 and 0$ are real numbers, then $-4$ is a complex number.
Thus, $-4$ is:
a real number;
a complex number