sentence: When both of them started to search for clues around the house , they did n't find anything interesting , but after a while , they had seen several paw prints and , at that moment , Michael remembered a fact : he had left his dog inside the house , but the puppy had disappeared !
modified: When both of them started to search clues around the house they did n't found out anything interesting , but after a while , they had seen several pawprints and in that moment Michael remembered a fact : He had been forgotten his dog inside the house but the puppy had disappeared !
transformation: PREP, PUNCT, VERB:FORM, PART, ORTH, PUNCT, PREP, PUNCT, ORTH, VERB:TENSE, VERB, PUNCT