1. The bird fell into the tree.
2. The bird fell in the tree.
3. The bird fell out of the tree.
4. The bird fell from the tree.
5. The bird fell off the tree.
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Are they all grammatical? Does 1 mean 2? Are the rest all the same in meaning?
Does sentence 1 mean that the bird fell out of the sky and down into a tree? If so, then it's correct. Sentence 2, though, means the bird was in the tree and fell to a lower branch in the same tree.
3 and 4 are correct and mean the same thing. 5 is strange, though. I've never heard or read that phrasing!