Four terms means four products, which are added up.
One term with an exponent: [tex]2x^4[/tex]
One term with a coefficient of five, let's make it a like term: [tex]5x^4[/tex]
One term with three factors: [tex]abx[/tex]
One constant: 7
Our expression:
[tex]2x^4 + 5x^4 + abx + 7[/tex]