<!DOCTYPE html>
<html>
<head>
<style type="text/css">
input{
margin-bottom: 12px;
}
input[type='text']{
margin-left: 12px;
}
input{
margin-bottom: 12px;
margin-top: 2px;
}
input + input{
display: none;
}
input:checked + input[type='text'] {
display: inline-block;
}
</style>
</head>
<body>
<form>
<label for=check1>Item 1</label>
<input id=check1 type='checkbox' value='1' /><input type='text' value='' /><br />
<label for=check2>Item 2</label>
<input id=check2 type='checkbox' value='2' /><input type='text' value='' /><br />
<label for=check3>Item 3</label>
<input id=check3 type='checkbox' value='3' /><input type='text' value='' /><br />
</form>
</body>
</html>