[误] Look, there are two sparrows on the tree.

　　[正] Look, there are two sparrows in the tree.

　　注：英语中，只有“长”在树上的东西才用介词 on，例如：There are lots of apples on the tree;其余均用介词 in，例如：The primitive built houses in the tree(原始人在树上建房子)。本例句也不例外。