rong>test sample</strong>&nbsp;should be given a score according to the following scale, known as the MOS (mean opinion score) scale for naturalness:</p>

<table>
	<tbody>
		<tr>
			<td align="center" width="100"><b>Score</b></td>
			<td width="200"><b>Quality of the Speech</b></td>
			<td width="300"><b>Naturalness</b></td>
		</tr>
		<tr>
			<td align="center">5</td>
			<td>Excellent</td>
			<td>Completely natural</td>
		</tr>
		<tr>
			<td align="center">4</td>
			<td>Good</td>
			<td>Mostly natural</td>
