Long ago, only the cat had the ability to trace its prey by scent（根据气味追踪猎物）. The other animals used their eyes to （发现）their prey. The dog wanted to learn the skill, so he went to visit the cat. The cat said yes to the dog's （要求）and asked him to stay in his house during the lessons. After a few （天）the dog thought that he could use the skill and wanted to go home.
"You haven't (学会)the skill yet, "said the cat.
" But I have to go home now, the dog said.
" All right," the cat said. " You may go back tomorrow but not today."
The next morning, when the dog came to say goodbye, the （猫的）wife told him the cat went out early in the morning but she didn't know （哪里） he went.
Actually, the cat hoped to test whether the dog had learned the skill. The dog started by (跟着)the footprints of the cat. However, the cat jumped from one rock to another and then (葳)himself in a tree.
The dog followed to the two rocks but he could not find any footprints there. He became （失望）He kept going round and round the tree. but he couldn't trace the cat.
The cat watched every move of the dog. Finally he said , "Look up! You have not （完全地）learned the skill!"
That's why the dog only knows how to trace its prey on the ground.
