it is a complete sentence I belive
The best revision to combine sentences two and
three is this one:
<span>
"Let freedom ring” is a phrase which is used many times in Dr.
Martin Luther King Jr’s speech that leads to an exciting conclusion.</span>
<span>
In order to construct correct compound sentences, you should omit words
that contribute to redundancy. </span>
The answer is the readers Senses. Because it helps us better imagine the settings as if we were there.