<em>polite- more <em>polite</em>- the most <em>polite</em>
</em>
<em>careful- <em>more careful</em>- <em>the most careful</em>
</em>
<em>quick- <em>quick</em>er - the <em>quickest</em>
</em>
<em>different-<em>more different-</em>- the most <em>different-</em>
</em>
<em>narrow- <em>narrower</em> - the <em>narrowest</em>
</em>
<em>pretty-<em>prettier</em>- <em>the prettiest</em>
</em>
<em>sad- sadder- the saddest
</em>
<em>big- bigger- the biggest
</em>
<em>happy- happier- the happiest
</em>
<em>nice- nicer- the nicest
</em>
<em>old- older- the oldest
</em>
<em>sweet-sweeter- the sweetest</em>