<h1 spellcheck="true"></h1>
spellcheck = true - will check for spelling errors.
spellcheck = false - will not check for spelling errors.
<div spellcheck="true">
<label>Escreva algo: </label><input type="text" size="50">
<br>
<label>Escreva outra coisa: </label><input type="text" size="50">
</div>
<br>
<label>Mais alguma coisa: </label><input type="text" size="50">