instruction:
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.
question:
Fossil fuels come in ____ major forms coal, oil and natural gas.
answer:
three


question:
Some children start asking questions when they're ____ or five years old.
answer:
four


question:
Insects go through either ____ or four stages.
answer:

three