"You speak and exclaim." was marked as incorrect. Putting an extra 'you' in there is both unnecessary and redundant.
Here "exclamas" is translated as "exclaim" while in an another sentence it is translated as "shout". What is the difference ?
No real difference. 'Clamare' means to shout, complain loudly, make noise with your voice etc.. Add the ex in front and it means to shout out, cry aloud, exclaim, etc.