1. First we have to select central atom.
w ʌ n WORD_BOUNDARY f ɜː s t WORD_BOUNDARY w iː WORD_BOUNDARY h æ v WORD_BOUNDARY t ə WORD_BOUNDARY s ɪ l ɛ k t WORD_BOUNDARY s ɛ n t ɹ ə l WORD_BOUNDARY æ t ə m WORD_BOUNDARY