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: Amphibians have ____ legs, and often look like reptiles.

Answer: four


Question: Perennials are plants that live more than ____ growing seasons.

Answer: two


Question: Most elements have ____ or more isotopes.

Answer:
two