Add a short extra stroke to ㅏ ㅓ ㅗ ㅜ to get ㅑ ㅕ ㅛ ㅠ, which add a quick "y" sound.
Read and say the ㅑ ㅕ ㅛ ㅠ rows (갸 겨 교 규 …) and tell them apart from 가 거 고 구.
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