Can we write Legend tag twice inside a fieldset tag?

Question

Can we write the <legend> tag twice in a <fieldset> ?
And can we include the <p> tag inside the <fieldset> ?

<fieldset>
    <legend>Feedback</legend>
    <p>Did you like it?</p>
    <input type="checkbox" name="level" value="low" />
    <label for="level">I didn't Like it.</label>
    <input type="checkbox" name="level" value="high" />
    <label for="level">Heck, Yes.</label>
    <legend>Subscribe for newsletter:</legend>        
    <input type="radio" name="newsletter" value="yes">
    <label for="newsletter">Yes</label>
    <input type="radio" name="newsletter" value="no">
    <label for="newsletter">No</label>
</fieldset>

Answer 1

Technically, 1 legend. Multiple p s are ok. See the technical summary here and check out the link to 'Flow content'.

Answer 2

Per the W3 specification: "The name of the group is given by the first legend element that is a child of the fieldset element, if any. The remainder of the descendants form the group." There is no indication that having multiple legend tags present would be invalid HTML, but I don't think it is a good idea to have more than one. And yes, it is fine to add p tags within fieldset. Take a look at the examples from the link I provided.