YOU SAID:
The dog want to eat the apple in the tree
INTO JAPANESE
犬は木のリンゴを食べたい
BACK INTO ENGLISH
dog wants to eat an apple on a tree
INTO JAPANESE
犬は木の上のリンゴを食べたい
BACK INTO ENGLISH
the dog wants to eat the apple on the tree
INTO JAPANESE
犬は木の上のリンゴを食べたがっている
BACK INTO ENGLISH
the dog wants to eat the apple on the tree
That didn't even make that much sense in English.