what r the important topics on measure for measure for MA exam?

You might want to examine the major themes of the play. I'll give you a few and then the link to the GradeSaver site for more detail.

Actions vs. words

The Duke, especially, announces that he is doing one thing, and then acts completely different from his stated intent. This calls forth questions why the Duke would be deliberately misleading, and what his overall intent for this deception of leaving the city is.

Corruption

The city in this play is corrupt, just as Angelo becomes so. This corruption seems to be the result of too much indulgence, or a belief that one will get away with one's crimes.

Vice vs. Piety

Several figures in the play seem to err either toward being too indulgent or too strict; the play attempts to punish those who are too licentious, and teach those who are too pious, by the time the end is reached.

in this work of art one is left to believe that mercy and justic are the most targeted issue,hence Angelo is left incharge of a corrupt city to impose strict rules that had been inactive for the past 14 years and judgement neccessarily to the crime commited.as an allegorical theme each character is awarded as a measure for measure ref:Methew 7 vs 2 it says :{for what judgement ye judge ye shall be judged and with what measure ye mete,it shall be measured to you again.}>