This radical shows a hill. This radical 阝 is always on the left of the hanzi. (Please note that this relatively similar radical ⻏ stands for “village” and is in the character always on the right.)
The plants 艹 are made by the sun 日 to be large 大 [= as long shadows] at sunset. - The very similar radical stands for sunrise. This seems bizarre, but can be argued based on the characters for morning 朝 in comparison to evening 暮.
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