The given sentence contains a typo which could be one of the following four types: (1) swapped letters of a word e.g. 'niec' is a typo of the word 'nice'. (2) missing letter in a word e.g. 'nic' is a typo of the word 'nice'. (3) extra letter in a word e.g. 'nicce' is a typo of the word 'nice'. (4) replaced letter in a word e.g 'nicr' is a typo of the word 'nice'. You need to identify the typo in the given sentence. To do this, answer with the word containing the typo.

Example Input: cat aitting on top of a red and black motorcycle outdoors
Example Output: aitting

Example Input: A red and tellow fire hydrant in a grass lawn next to a sidewalk and two street signs attached to a wood post.
Example Output: tellow

Example Input: a couple of zebras that are laying on the gronud
Example Output:
gronud