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leaf; blade (of grass); (pine) needle
marijuana; cannabis
秋になって、葉っぱが黄色くなりました。
When autumn came, the leaves turned yellow.
この木の葉っぱはとても大きいですね。
The leaves of this tree are very big, aren't they?
風で葉っぱが地面に落ちています。
The leaves are falling to the ground in the wind.