The main idea (theme) is that there once was a boy named Tom that got tickled so much he fell on traintracks and died. He used ambiguity in the last 3 lines. The deeper meaning is that he rolled on to a train track and a train was coming, but he was laughing so hard the train ran over him and he died, so he’s not ticklish anymore. The poem uses couplets that rhyme. The poem also uses elegy in the last 4 lines, using couplets that represent death indirectly. Also, irony is used because the reader is able to understand the deeper meaning using simply prior knowledge about the event and their imagination.