JSFiddle - React, Tailwind, and code Playground

JavaScript

var sentenceOne = "Pretty kitty doesn't like you!";
var sentenceTwo = "Preachy cat loves you.";

alert(startWith(sentenceOne, sentenceTwo, "Pre"));

function startWith(sentenceOne, sentenceTwo, pattern) {
    return !(sentenceOne.indexOf(pattern) || sentenceTwo.indexOf(pattern));
}