The Unity of action: (the play has no or few subplots) All plays I find have a subplot. But the most common is the romance subplot. Whether it be a subplot to have romance between two characters or a love triangle there is usually that subplot. This usually does not however, take away from the main plot but is rather an add on to the main plot. usually though there is not to many this way it does not take away from the main storyline and doesnot over complicate itself within the main story.
The Unity of place: (the play should be set in one relative place) It makes it easier if the play is staged in as few locations as possible. Thus making it easier for the audience to understand where they are and whats going on. For example MOV was usually staged indoors this way if we were in padua or manuta we only had to be told rather then figureing it out another way. staged plays are differnet then in movies because in a movie you simply move locations of filming where as in a play you re-set the stage. so when stageing a play you make it as simple as possible.
The Unity of time: (the play should take place over no more then 24 hours) I don't know if I can agree with this becuase different plays require different amounts of time. and it is easy to turn out the lights and turn them back on showing that one day has gone and another has come forth. however backin Aristotle's day maybe they only had outdoor theaters so it had to be in a 24 hour time limit. If you were to make a play happen in a 24 hour time period it might be easier to understand but it would seem to me to be rather abrupt and sudden. the time limit thing might work with COE but not so much with taming of the shrew. which is supposed to be set within a week of at the very least a few days.