I added the form tag for inline forms, it works when you have enough room on the page for one line.
<form class="form-inline" role="form">
<div class="form-group">
<p>My name is
<input type="text" placeholder="Name" name="name" class="form-control" style='display:inline;'/>
from USA. And I'm <input type="text" name="age" placeholder="21" class="form-control" style='display:inline;'/> years old.
</p>
</div>
</form>
Here's some more information explaining it from getbootstrap.com.
"Add .form-inline to your for left-aligned and inline-block controls. This only applies to forms within viewports that are at least 768px wide.
Requires custom widths
Inputs, selects, and textareas are 100% wide by default in Bootstrap. To use the inline form, you'll have to set a width on the form controls used within."
http://getbootstrap.com/css/
Works in jsfiddle when it's wide enough.