php captcha like go back to page
<p>I have a website, I want to make a form type box, where the user has to enter a word (like "monkey") then click sign in.  If they enter it correctly, then they can see the log in page, if not, then they return to the page with the captcha.</p>

<p>I am not sure how to send them back to index.html using php if they are incorrect.  </p>

<p>How do I do this?</p>
