Understanding is a relation between the knower and an object of understanding. Both comprehension and understanding can be used to talk about someone's ability to understand something. The meaning of understanding is a mental grasp :
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Understanding implies abilities and dispositions with respect to an object. Understanding a concept means you get it. Or about how something works:
How to use understanding in a sentence.
Your understanding might be that your mother will always drive you to school if you miss the bus. He noted bond's apparent lack of. Comprehension usually used with of. Knowledge about a subject, situation, etc.