在一棵大树上，有一些鸟宝宝。

In the big tree, there are some baby birds.

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他把狗栓在一棵大树上。

He tied his dog to a big tree.

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我们在那些较大的树的树心上砍出了一些洞作为小屋，并用大树枝和嫩枝，在一棵树上建了一间大屋，这棵树已经倒了下来，压在另一棵树上。 这些劳作很艰苦。

We cut out holes in the center of larger trees, to make little huts, and built a large one out of large branches and twigs, upon a tree that had fallen down and was resting on another.

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