Factor $6 n+4 n^{3}$

Step 1 ：The given expression is a polynomial $6 n+4 n^{3}$.

Step 2 ：To factorize it, we need to find the common factors in both terms.

Step 3 ：The common factor here is $n$.

Step 4 ：After factoring out $n$, we can simplify the expression.

Step 5 ：The factored form of $6 n+4 n^{3}$ is $oxed{2n(2n^2 + 3)}$.