instruction:
Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
question:
Chewing insects such as dragonflies and grasshoppers have two many sets of jaws.
answer:
Chewing insects such as dragonflies and grasshoppers have how many sets of jaws?


question:
The term amines is used to describe molecules that contain carbon-nitrogen bonds.
answer:
What term is used to describe molecules that contain carbon-nitrogen bonds?


question:
Varicose veins are veins that become enlarged because the valves no longer close properly.
answer:
Varicose veins are veins that become enlarged because the valves no longer do this?