让我们来看看这些可能改变世界的青少年发明。

Let's have a look at these teenage inventions that might change the world.

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让我们来看看世界各地的一些生日习俗。

Let's look at some birthday customs around the world.

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在1920年代新的思想和生活方式不断涌现，让我们一起来看看哪个年代人们眼中的世界吧。

New ideas and patterns of life developed in the 1920's and in the way that people looked at the world.

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