sharks
Worry a little bit every day and in a
lifetime you will lose a couple of years.
If something is wrong, fix it if you can.
But train yourself not to worry: Worry never
fixes anything.
But man is not made for defeat, a man can
be destroyed but not defeated.
可是一个人并不是生来要给打败的，你尽可以消灭他，
可就是打不败他。
Sharks
Introduction
Sharks have lived in the oceans since before
dinosaurs walked on Earth. Hundreds of kinds
of sharks can be found all over the world.
Sharks are fish, but their skeletons are
made of cartilage(软骨) instead of bones.
Cartilage is what gives human ears their
shape. Unlike most fish, sharks have rough
skin. Sharks have a good sense of smell.
They also see well in the dark. Sharks can
sense other animals moving in the water.
Description
Sharks come in many sizes. Some sharks are
only a few inches long. The huge whale shark
is the largest fish in the world. Many sharks
are dark on the top and light on the bottom.
This shading makes it harder for other animals
to see them.
Sharks swim by swinging their tails from
side to side. Fins help sharks steer(控制方向),
turn, and keep their balance.
Eating
Most sharks have many rows of teeth. When
one tooth breaks off, another one moves up
to take its place.
Most sharks eat fish. Large sharks eat sea
lion, dolphins, and other sharks. Some sharks
eat shellfish(贝壳). These sharks have flat
teeth for crushing(捣碎) shells. The huge whale
shark has tiny teeth but doesn't use them when
eating. It swallows very small ocean plants
and animals that float near the ocean's surface.
Shark Attacks
Many people are afraid of sharks, but most
sharks do not attack humans. Great white
sharks are one of the few kinds of sharks
that are dangerous to people.
Shark hunting
People hunt sharks for their skin, oil, and
teeth.
Many people eat shark meat, and shark fins
are used to make soup.
Many kinds of sharks are now in danger of being
completely killed off. Sharks are an important
part of the balance of life in the world's oceans.
They have as much right to live as other animals.