how to replace all instances of text in javas code example

Example 1: javascript replace all occurrences of string

function replaceAll(str, find, replace) {
    var escapedFind=find.replace(/([.*+?^=!:${}()|\[\]\/\\])/g, "\\$1");
    return str.replace(new RegExp(escapedFind, 'g'), replace);
}
//usage example
var sentence="How many shots did Bill take last night? That Bill is so crazy!";
var blameSusan=replaceAll(sentence,"Bill","Susan");

Example 2: replace all js

let a = 'a a a a aaaa aa a a';
a.replace(/aa/g, 'bb');
// => "a a a a bbbb bb a a"