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: Human malaria is caused by ____ species of Plasmodium . .

Answer: four


Question: Knee arthroscopy is used basically in ____ ways.

Answer: three


Question: Pineapple plants have ____ different kinds of roots.

Answer:
two