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: A bedroon is well-furnished with a four-post bed, sitting chairs, a desk and a coffee table.
Example Output: bedroon

Example Input: Some people are playing frisbee in a vallye.
Example Output: vallye.

Example Input: a colck on a tower on a city street
Example Output:
colck