I was taught that there shouldn't be any commas before or after prepositions. Why is that in some sentences such as sentence 1 below, a comma before "of" is permitted?
Detective Polly found that, of the hundreds of cases of malaria near the river, all but three involved near the contaminated pump.
Or for sentence 2, why do we have to have a comma between "program" and "from"?
They now operate from 12 to 2pm, and the government funds every aspect of the program, from the jerseys to the coaches.
Or for this sentence...why is that we can't have a comma between "VP" and "about"?
I signaled to the VP about the wrinkle on his tie.