Classify the expression: $5 x^{3}+2 x-3$ Quadratic expression Linear expression Cubic expression Exponential expression

Step 1 ：Classify the expression: \(5 x^{3}+2 x-3\)

Step 2 ：This is a polynomial expression. The degree of the polynomial is determined by the highest power of x. In this case, the highest power of x is 3, so this is a cubic expression.

Step 3 ：Final Answer: \(\boxed{\text{Cubic expression}}\)