<section>, <article>, and <div>? <nav> tag? <aside> tag? <header> and <footer>? <figure> and <figcaption>? <blockquote> tag? cite attribute? id attribute? class attribute? id and class? <base> tag? <link> tag? rel attribute? <script> in head vs body? defer in script? async in script? <noscript> tag? <fieldset> tag? <legend> in forms? enctype in forms? multipart/form-data? required attribute? placeholder? pattern attribute? <datalist>? <datalist> and <select>? <output> tag? <progress> tag? <meter> tag? tabindex? contenteditable? <address> tag? <mark> tag? <time> tag? <code> tag?