instruction:
You are given a sentence and your task is to generate another sentence that supports the given input.
question:
Average continental crust is about 35 km thick;
answer:
The earth's continental crust, on average, is 35 kilometers thick.


question:
Features of pollen grains used in identification are size, shape, thickness of the exine (outer wall) and intine (inner wall) of the pollen grain.
answer:
Each pollen grain has two coverings: the exine (thicker, outer layer) and the intine.


question:
An amine denotes  an organic compound having a nitrogen atom singly or double bonded to a carbon atom and wherein the carbon atom bonded to the nitrogen atom is devoid of a double bond to oxygen, sulfur, selenium, or tellurium or triple bond to nitrogen.
answer:

Amines are classified according to the number of carbon atoms bonded directly to a(n) nitrogen atom.