阅读下面这首宋词，完成后面题目。

鹧鸪天 正月十一日观灯

姜夔

                                                       巷陌风光纵赏时，笼纱未出马先嘶。白头居士无呵殿，只有乘肩小女随。

                                                       花满市，月侵衣，少年情事老来悲。沙河塘上春寒浅，看了游人缓缓归。

0.36÷0.9=____÷9

Only when he had done it ______ that he had made a mistake.

_______ originally as the biggest defense work in ancient China, the Great Wall today has become one of the must–see places for visiting foreign leaders to the country in the past six decades. Obama is the fifth US president _______ the man-made wonder.

下面关于我国各民族分布的说法，正确的是（    ）