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.
Tip: Go to the radicals that are contained in this character and learn all the characters with this radical systematically!
Vocabulary
摸索
mō suo
to feel about; to grope about; to fumble; to do things slowly
4214
抚摸
fǔ mō
to gently caress and stroke; to pet; to fondle
4215
捉摸
zhuō mō
to predict (often uncertain); to grope (for the truth); to fathom; to ascertain
4216
顺藤摸瓜
shùn téng mō guā
lit. to follow the vine to get to the melon; to track sth following clues
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