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:
Most insects have one or ____ pairs of wings.
answer:
two


question:
Differentiation is caused by the energy going in ____ directions.
answer:
two


question:
Normal adults appear to require six to ____ hours of sleep per day on average.
answer:

eight