Top: sinking/going down 莫 (The plants 艹 are made by the sun 日 to be large 大 [= as long shadows] at sunset.), bottom: sun 日 [Notice: means sunrise such as in 'morning 朝']
Mnemonic
The sinking sun means sunset. [OR: The plants 艹 needed from one sun 日 to the next big 大 sun 日 are the life circumstances.]
The plants 艹 are made by the sun 日 to be large 大 (= as long shadows) at sunset. - Please be aware that this very similar radical stands for the sunrise.
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