Because Japan does not allow women to take the throne, Sayako must leave the imperial family when she marries Kuroda, a childhood friend of her brother.

日本不允许女性继承王位，因此，纪宫公主嫁给黑田庆树后必须离开皇室，黑田庆树是她哥哥儿时的朋友。

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After Liu Xun ascended the throne, he made Imperial Concubine Xu his queen.

刘询承皇位以后，立许妃做皇后。

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In the extraordinary honor of the meeting with Their Imperial Majesties, the Emperor and Empress, on the 20th anniversary of his ascension to the Chrysanthemum Throne.

我还有幸在天皇即位20周年之际会见天皇和皇后陛下。

youdao

The Ottoman dynasty did not observe primogeniture (the right of the first-born son to the throne), so in principle the throne was available to any imperial son.

BBC: Uncover the secrets of Topkapi Palace

It is actually a huge museum with the largest collection of imperial treasures in the country, including the superb Dragon Throne the emperor sat on and Buddhas bedecked with almost every precious metal and gemstone imaginable.

BBC: Beijing's once Forbidden City

The obvious solution would be to change the Imperial House Law so that a female could accede to the throne.

CNN: AN HEIR OF CHANGE IN JAPAN