Whether the sound came from his head or from the hollow tree, that no one could say with certainty.

没有人能肯定地说，这声音是从他的脑袋里发出来的呢，还是从空树里发出来的呢？

youdao

She walked under the apple tree. Suddenly, an apple fell on her head.

她从苹果树下走过，突然，一个苹果落在她的头上了。

youdao

We hit the tree head-on.

我们迎面撞到了树上。

《牛津词典》

"He skis off, he turns around to get a pass, he slams into a tree head first, he falls down unconscious, " reports Hay, who says he was a few feet away.

CNN: Tragedy Strikes Again

The tree that carried my ax head did not die, but it lost a major stabilizing part of its structure.

FORBES: We're All In The People Business (The Parable Of The Ax)

Friday, a car traveling south on the Garden State Parkway skidded off the road in Hazlet and ran into a tree, causing a fatal head injury to the rear passenger, said Sgt.

WSJ: Officials Urge Caution as Snow Starts Falling