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: Presidential elections take place every ____ years.

Answer: four


Question: Plants produce seed at ____ years of age.

Answer: eight


Question: Most paleontologists speak of ____ major episodes that occurred millions of years ago.

Answer:
five