JSFiddle - React, Tailwind, and code Playground

HTML

<style type="text/css">
#otherJobType {
    display:none;
}
</style> 

<script type="text/javascript">
function jobType(value){
        if (value == 'Other') {
            document.getElementById('otherJobType').style.display = 'block';
        } else {
            document.getElementById('otherJobType').style.display = 'none';
        }
    }
</script>

<select id="jobType" name="jobType" onchange="jobType(this.value);">
    <option value="option 1" selected>Option 1</option>
    <option value="Other">Other</option>
</select>

<input name="otherJobType" id="otherJobType" type="text" size="50" value="Please specify job type" onblur="if (this.value=='') { this.value='Please specify job type' }" onclick="if (this.value=='Please specify job type') { this.value='' }" />