You could use a sign language thing for "Drink" that looks sort of like the act of drinking but you can't use a sign language word for "Country" that looks like a country, or for "Idea" that looks like an idea.

你可以用看起来像喝这个动作的手语,来表示"喝",但你无法用看起来像国家的手语,来表示"国家",或用看起来像想法的手语来表示"想法"

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