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It was built in the 18th century and rebuilt later by the architect John Nash. The first Queen to live there was the young Queen Victoria. Above the State Entrance is the central balcony where the Royal Family appears on occasions of national importance. The Royal Standard flying over the building is the sign that the Queen is in the residence. What is it?

я часто задавал себе вопрос......? Я учусь в школе.....?закончить предложения?)