某村民柴刀砍伤左腿，8小时后送医院急诊，检查左大腿有5cm长的伤口，尚整齐，内粘较多

                                                                 Humpback whales

     Humpback whales are sometimes called performers of the ocean.This is because they can make
impressive movements when they dive.The name “humpback”, which is the common name for this whale,
refers to the typical curve shape the whale's back forms as it dives.
     Sometimes the humpback will dive with a fantastic movement known as a breach.During breaching
the whale uses its powerful tail flukes to lift nearly twothirds of its body out of the water in a giant leap.A
breach might also include a sideways twist with fins stretched out like wings, as the whale reaches the
height of the breach.
     A humpback whale breathes air at the surface of the water through two blowholes which are located
near the top of the head.It blows a double stream of water that can rise up to 4 metres above the water.
     The humpback has a small dorsal fin located towards the tail flukes about twothirds of the way down
its back.Other distinguishing features include large pectoral fins, which may be up to a third of the body
length, and unique black and white spots on the underside of the tail flukes.These markings are like finger
prints: no two are the same.
     Humpback whales live in large groups.They communicate with each other through complex “songs”