#### Answer

$\underline{\text{negative}}$

#### Work Step by Step

Read and observe the following situation:
$1 \lt 3$
Multiplying $-2$ to both $1$ and $3$ gives $-2$ and $-6$, respectively.
Note that $-2 \gt -6$.
Notice that when a negative real number is multiplied to both sides of an inequality, the inequality symbol changes to the opposite direction (or flips).
Thus, the missing expression in the given statement is $\underline{\text{negative}}$.