instruction:
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.
question:
Som elephants are playing in the water next to a waterfall.
answer:
Som


question:
An eklderly woman celebrates her 90th birthday with a cake.
answer:
eklderly


question:
a white toilet a toilet roll and a sigb
answer:

sigb