sentence: First I would like to introduce myself . My name is Joaquín Gutiérrez and I want to tell you why my favourite sport is football , which is a sport that I have practiced since I was six years old .
modified: First I would like to intoduce myself , my name is Joaquín Gutiérrez and I tell you why my favourite sport is football which is a sport than I have practiced since I was six years old .
transformation: SPELL, PUNCT, VERB, PUNCT, OTHER