<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<form class="form-horizontal">
<fieldset>
<legend>Form Name</legend>
<div class="form-group">
<label class="col-md-4 control-label" for="vezeteknev">Vezetéknév</label>
<div class="col-md-4">
<input id="vezeteknev" name="vezeteknev" type="text" placeholder="" class="form-control input-md" required="">
</div>
</div>
<div class="form-group">
<label class="col-md-4 control-label" for="keresztnev">Keresztnév</label>
<div class="col-md-4">
<input id="keresztnev" name="keresztnev" type="text" placeholder="" class="form-control input-md" required="">
</div>
</div>
<div class="form-group">
<label class="col-md-4 control-label" for="cegnev">Cégnév</label>
<div class="col-md-4">
<input id="cegnev" name="cegnev" type="text" placeholder="" class="form-control input-md">
</div>
</div>