<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<form name="form" method="post">
<div class="row form-group">
<input class="col-md-3" type="text" name="name" onfocus="if(this.value=='имя'){this.value = '';}" onblur="if(this.value==''){this.value='имя';}" value="имя"/>
<input class="col-md-3" type="text" name="phone" onfocus="if(this.value=='телефон'){this.value='';}" onblur="if(this.value==''){this.value='телефон';}" value="телефон"/>
<input class="col-md-3" type="text" name="email" onfocus="if(this.value=='e-mail'){this.value='';}" onblur="if(this.value==''){this.value='e-mail';}" value="e-mail">
<button class="col-md-3 btn btn-success" type="submit">Отправить</button>
</div>
</form>
