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hornworm (caterpillar of a hawk moth); (hairless) caterpillar
葉の裏に大きな芋虫がついていた。
A large caterpillar was on the underside of a leaf.
芋虫は成長するとやがて蛾になる。
Caterpillars eventually become moths when they grow.
子供が芋虫を怖がって泣き出した。
The child started crying because they were scared of the caterpillar.