sharp和shark押____（）

A．All sharks have teeth.

B．A shark can have six rows of teeth.

C．A shark can have hundreds of teeth.

D．All sharks have extremely sharp teeth.

A．A shark attacks a person for no reason.

B．A shark attacks a person every time it sees one.

C．A shark attacks a person only if it is bothered.

D．A shark attacks a person only at night.

What is the key to the shark’s swift locomotion in water？

A．The skin.

B．The tail.

C．The muscle.

D．The jaw.

Different from most fishes, shark's body is not upheld by ______.

A．fiber

B．bones

C．cartilage

D．skeleton

Which of the following sharks is the mast common shark？

A．The whale shark.

B．The basking shark.

C．The spiny dogfish shark.

D．The great white shark.

A．Because it is also full of blood pressure.

B．Because it is also filled of air pressure.

C．Because it is also inflated by pressure.

D．Because it also can be used again and again.