a. What role does the hearer play in making sure the speaker's utterance, sound and message is correctly understood?

b.Name one strategy the hearer can use to increase understanding.

I would appreciate some ideas, but I think the key here is listening and asking questions would be a good start. Any thoughts?

4 answers

Yes ... it's called active listening.

http://www.google.com/search?q=active+listening&ie=utf-8&oe=utf-8&aq=t&client=firefox-a&rlz=1R1GGGL_en___US357

Lots of ideas in these search results.
Thank you for your help!
You're very welcome.
Here is another article:

http://www.members.cox.net/dagershaw/lol/Listener.htm

I hope this helps a little more.