11．The seal lying on top of the ice doesn't stand a chance．Knocked into the sea，the seal becomes a meal for one of the oceans top hunters-the huge orca，or killer whale．
Orcas hunt almost everything from fish to seals，sea lions，penguins，sharks，and even other kinds of whales．Depending on the season and where they are，their diet varies-some orcas eat more fishes than seals and penguins．But wherever they are in any of the world's oceans，average-sized orcas may eat about 500 pounds of food a day．Orcas have many hunting techniques，and striking seals off ice is just one of them．
Often referred to as wolves of the sea，orcas live and hunt together in family groups，much like a pack of wolves．Groups of orcas work together to drive fish into a compact area so that they're easier to eat．They will also hit their tails onto the water's surface，causing a wave to wash penguins or sea lions into the water．
Orcas'teeth，numbering about 45 and each measuring about 3inches long，are shaped for tearing prey （猎物） Orcas do not chew their food．They can swallow small seals and sea lions whole．The prey slides down the orcas'throats!The color pattern of orcas may help them at-tack their prey．Their backs are black but their stomachs are white．Animals looking down on an orca from above，such as a seal on ice，might not see it because the whale's dark back blends with the water below．
On the other hand，the whale's white underside combines with the light streaming down into the sea from the surface，making it hard to spot from below．With orcas camouflaged so well，those prey fish，penguins，or seals are likely to miss the danger heading their way，as the killer whale once again proves it is the oceans'superbly designed hunter．
28．According to the text，we know orcas areD．
A．good at using their teeth
B．the most cruel hunters in the world
C．big whales who don't hunt other whales
D．skillful hunters who like hunting many creatures
29．Which word can be used most probably to describe orcas when they are hunting？A
A．Cooperative
B．Incompetent．
C．Swift．
D．Careful．
30．What is the main idea of Paragraph 4？C
A．The reasons why orcas hunt seals．
B．The environment where orcas live．
C．The features of what orcas look like．
D．The ways of how orcas hunt animals．
31．What does the underlined word"blends"in Paragruph 4 mean？B
A．Meets．
B．Mixes．
C．Struggles．
D．Equips．
分析 短文主要描述了逆戟鲸的捕食对象以及其狩猎方式进行描述．
解答 28．D，推理判断题，根据句子Orcas hunt almost everything from fish to seals，sea lions，penguins，sharks，and even other kinds of whales可知，逆戟鲸是熟练的捕食者，故答案为D．
29．A，推理判断题，根据句子Often referred to as wolves of the sea，orcas live and hunt together in family groups，much like a pack of wolves可知，逆戟鲸是群体作战的，因此它们是合作的，故答案为A．
30．C，主旨大意题，第四段主要描述了逆戟鲸的牙齿等特点，故答案为C．
31．B，词义猜测题，根据语境指的是逆戟鲸的背部和水混在一起，导致其他动物看不到它们，因此可以推测其为"混合"的意思，故答案为B．
点评 解答任务型阅读理解题，首先对原文材料迅速浏览，掌握全文的主旨大意．因为阅读理解题一般没有标题，所以，速读全文，抓住中心主旨很有必要，在速读的过程中，应尽可能多地捕获信息材料．其次，细读题材，各个击破．掌握全文的大意之后，细细阅读每篇材料后的问题，弄清每题要求后，带着问题，再回到原文中去寻找、捕获有关信息．最后，要善于抓住每段的主题句，阅读时，要有较强的针对性．对于捕获到的信息，要做认真分析，仔细推敲，理解透彻，只有这样，针对题目要求，才能做到稳、准．
