In 1790, a bunch of different troupes came to Beijing to celebrate the eightieth birthday of Emperor Qian Long.

直到1790年 群风格各不相同剧团来京城庆祝乾隆皇帝大寿。

" I wish you'd been there when we went down to present him with his portrait on his eightieth birthday. It really was a memorable occasion" .

" 那次他岁生日，我们把他幅画像送去给他时候，可惜你不在场。 那真是人难忘场面。"

Because the Moon has only an eightieth of the Earth's mass, it requires 97% less energy to travel the quarter of a million miles from the Moon to Earth-orbit than the 200 mile-journey from Earth's surface into orbit!

因为月球重只有地球1/8，因此，从月球到地球25万英里所消耗能量要比从地球表面进入地球轨道200英里所耗能量少97%。