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stomach and intestines; gastrointestinal tract; digestive organs
胃腸の調子が悪く、食事を控えた。
My stomach was upset, so I ate less.
冷たい飲み物は胃腸に負担をかける。
Cold drinks put a strain on the digestive system.
祖母は胃腸が丈夫で何でも食べる。
My grandmother has a strong stomach and eats anything.