The entire family of rays is well armed． The eagle ray's tail has teeth sharp en

The entire family of rays is well armed． The eagle ray's tail has teeth sharp enough to cut off a man's arm． The gray ray can snap its seven-foot tail like a whip． The torpedo ray discharges an electrical current strong enough to knock a man down．

The stingray has a barb or spine in its tail, with teeth along the edge． At the base of the teeth is a poison gland． When the flexible tail swings upward, the spine can cause a painful wound almost as dangerous as a poisonous snakebite．

A stingray has been known to lash out so savagely with its tail that the spine sank into an oar two feet above the water． Another ray pierced a boat． One fisherman attacked by a ten-foot ray was struck with such force that the barb went right through his leg, bone and all．

1．Details in the selection prove that rays are________．

A．intelligent B．well nourished C．well armed D． huge

2．The main protection of the torpedo ray is its______．

A．light weight B． speed of movement C． ten-foot tailD． electric current

3． The stingray is protected by ________．

A．a spine in its tail B．poison in the spine

C．Both A and BD．Neither A nor B

4．The stingray's protection is like that of______．

A． a tiger B． a rattlesnake C．a kangaroo D． an eagle

5．One stingray's spine_______．

A．pierced right through a boat B． sank a boat

C．Both A and BD．Neither A nor B

6．The fisherman tangled with a ray that______．

A．broke his oar in two B． lifted the boat out of the water

C．pierced his leg bone D． All of the above

7．The author's purpose in the third paragraph is to show the strength of the stingray's_______．

A． barb B． poison C． battery D．All of the above

8．The author bases his story on_____．

A． guesses B． examples C． figures D．None of the above

试题答案

答案：C;D;C;B;A;C;A;B