Sister Mary Louise is teaching her class how to write a book and goes to great lengths to explain that a book must have a little religion, a little sex and a huge mystery. She then asks them to work out a plot and start on the first chapter, and reminds them again, a little religion, a little sex and a big mystery. After 5mins, the blonde in the class put her hand up and said. ?Finished sister?. Sister in disbelief asked her to read it out to the class, whereupon the girl stood up and read. ?My God, I?m pregnant, who done it?