upside down的意思是：颠倒的。
upside down的意思是：倒置地，颠倒的。读法为：美：/psad dan/。
例句：
1、His eyes were open and everything he saw was upside down.
他的眼睛睁着 他看到的一切都是颠倒的。
2、They're lenses because they're convex vessels, and when they're full of water, they act as a lens and you see the horizon in them, upside down and backwards.
它们是透镜，因为它们是凸面容器，当它们盛满水后，它们可作为透镜使用，你可以看到它们里面上下颠倒的地平线。
3、The painting was hung upside down.
这幅画挂颠倒了。
4、The canoe floated upside down on the lake.
独木舟底朝天漂浮在湖面上。
5、Every pill made my insides turn upside down.
每片药都使我的胃翻江倒海。
