Left: mouth 口, right: (exclamation of approval) 阿 (From the elevated point of a hill 阝 there is the possibility 可 [because of better sound transmission] to: shout)
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.)
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