It is no more than a series of select lists from which the user may choose an option.
Code:
<select id = "list1">
<option value = "">Choose a recipient</option>
<option value = "Father">Father</option>
<option value = "Mother">Mother</option>
<option value = "Grandma">Grandma</option>
</select>
<input type = "button" value = "Generate Letter" onclick = "generate()">
<br><br>
<div id = "letter">
</div>
<script type = "text/javascript">
function generate() {
var r = document.getElementById("list1").value;
if (r!="") {
var message = "Dear " + r + ",";
document.getElementById("letter").innerHTML = message;
}
}
</script>
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