Propositional logic and connectives(translating to english)
The first thing to say is that in propositional logic every statement will have a truth value.

If (P or Q or R) evaluates to True (which it doesn't have to) then a natural English way to translate would be:


  Either you have the flu, you miss the final examination or you pass the course.


Note that this "or" is clearly inclusive - meaning that it is possible that more than one of those things happens but at least one must. To make that clear beyond doubt in natural English you might structure the sentence using "at least". This will be much more long winded but avoids the person you are communicating with thinking that you might mean exclusive "or" (e.g. the type of "or" used in "true or false" - it can be one or the other but not both). If you wanted to account for this you might say something like:


  At least one of the following is true: you have the flu, you miss the final examination or you pass the course.


For your second case what you said is not very natural. You would typically hear someone say:


  You won't pass the course if you have the flu or miss the final examination.


If you are supposed, for whatever reason, to structure the answer as you did, the commas should be removed after your "if" clauses. This would be better:


  If you have the flu then you do not pass the course, or if you miss the final examination then you do not pass the course.