Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.
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Question: Marriage is the legal union of ____ people.

Answer: two


Question: Neurofibromatosis appears in ____ forms.

Answer: two


Question: Cats can produce up to ____ litters a year from the age of one.

Answer:
three