import js into jquery code example

Example 1: how to import jquery in js file

var script = document.createElement('script');
script.src = 'https://code.jquery.com/jquery-3.4.1.min.js';
script.type = 'text/javascript';
document.getElementsByTagName('head')[0].appendChild(script);

Example 2: jquery import js file

$.getScript('ajax/test.js', function() {
    alert('Load was performed.');
});