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.
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Question: A bed in a adrk room in front of a window with the sun shining in.

Answer: adrk


Question: a doble deaker bus turning a corner of a road

Answer: doble


Question: A peeson walks with a backpack being followed by a dog.

Answer:
peeson