MUST - MUSTN'T - CAN - CAN'T


1
When they visit a museum, tourists eat snacks.
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They drink sodas.
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They listen to the guide.
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They respect the rules.
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They take photos.
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The children run around the statues.
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They ask stupid questions.
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They use their mobile phones.
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They listen to their MP3 players.
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They buy souvenirs at the gift shop.