At 46, king Willem-Alexander is the youngest monarch in Europe. He is also the first Dutch king in more than a century.

国王威廉·亚历山大，46岁，是欧洲最年轻的君主。他也是一个多世纪以来荷兰首位国王。

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King Willem-Alexander's marriage when he was crown prince was also controversial.

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The five-minute song - Koningslied in Dutch - was due to be performed in the presence of the new king and queen on the day of Willem-Alexander's swearing-in at 19:30 (17:30 GMT).

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When Willem-Alexander becomes king, 9-year-old Catharina-Amalia will be next in line.

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