The character for tall 大 shows a person 人 with outstretched arms 一. If you shift the lower strokes towards each other, you can get the: woman 女. The wider lower area can be understood as female hips?
Shows a pregnancy belly in a side view - The meaning of this radical is based on 孕 (yùn), which means: "pregnancy". It is read such that the child 子 comes out of the womb 乃.
Tip: Go to the radicals that are contained in this character and learn all the characters with this radical systematically!
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