What do you do with a wet umbrella in Japan?
Leave it at the door. Shops and museums put out umbrella stands or a machine that sleeves it in plastic, and carrying a dripping umbrella through a shop is what people notice. Outside, hold it upright at your side rather than swinging it, and shake it off before you step in.
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Say it in Japanese
Show the card to the staff. The Japanese, how to read it, and the recorded voice.