Creating a small page that generates 3 random words from 3 seperate lists at the click of a button

I coded a little in college but forget basically everything. I want to create a bare bones page that has a button labeled "Generate" That will give you a 3 word sentence from 3 separate lists...basically :

list one has "1, 2, 3, 4, 5, 6, 7, 8, 9" list two has "a, b, c, d, e, f, g, h, i" list three has "car, horse, gym, fair, boat"

You press "generate" and it puts three of those values into one sentence... example : 4 h boat after pressing generate...how can I do this?