阅读理解。 The elephant is the largest animal to walk on Earth. An elephant can carry a load of 1,200 pounds (磅). They eat 300 pounds of food a day. An elephant baby can weigh 200 pounds at birth. Elephants can live up to 70 years. Elephants can be trained to carry logs with their trunks (象鼻), and have been used in the forestry industry in Asia for many years. Elephants use their ears as a cooling system. Blood  flows through veins (静脉) in the ears and as the elephant flaps (拍击) his ears, the blood cools and flows through his body to cool off other parts. There are two kinds of elephants: the African elephant and the Indian elephant. African elephants can be identified (识别) by the larger ears. The African elephant grows up to 10 feet tall and weighs as much as 12,000 pounds. The Indian elephant grows up to 9 feet tall, and weighs up to 8,000 pounds. It's easy to identify because of its smaller ears. Most circus (马戏团) elephants are Indian elephants. Another name for the Indian elephant is the Asian elephant. 1. Elephants can live up to _______ years. 2. Elephants use their _______ as a cooling system. 3. There are two kinds of elephants: the African elephant and the _______ elephant. 4. The _______ of the African elephant is as much as 12,000 pounds. 5. It's not _______ to identify the Indian elephant from its smaller ears.