Complex sentence: At first, Mr. Fox thinks that Ted is trying to sell him pornography, and offers him £25 for the collection, but then Ted tells him that he just wanted him to see what Mustard's been doing on his rounds.
Split into simpler sentences: At first, Mr. Fox thinks that Ted is trying to sell him pornography, and offers him £25 for the collection. When Ted tells him that he just wanted him to see what Mustard's been doing on his rounds.