当x______时，-x没有意义．

阅读理解。

     There was little rain in some place for two years and a lot  of people died  of  hunger.  So a man

reported a famine (饥荒) to  an official (官员) .  The official asked,   "How  much  wheat have you

harvested?"

     "Thirty percent of the normal yield(正常产量的30%)," the man replied.

     "How much cotton?"

     "Twenty percent." 

    "How much rice?"

     "Twenty percent."

     The official got mad, " You've  already had  seventy  percent of the harvest,  how dare (敢) you

trump up(谎报)famine then?"

     The man said, "I've  never seen  such  a  terrible famine in my life of a hundred and several scores

of years."

     "How could you have lived so long?" asked the official.

     "Look, I'm over seventy years old.  My  eldest son is  over  forty and my second son is over thirty.

The total(总数)is a hundred and several scores of years." All the people hearing this had a good laugh

over that.

1.A great ______ happened in the place.

A. flood

B. disease

C. drought

D. war

2.The man said ______.

A. people had a bad harvest

B. some of the crops were bad

C. people lost their farms

D. people had little food

3.The word "mad" in the story means ______.

A. sad

B. angry

C. happy

D. excited

4.The official didn't think ______.

A. the people were hungry

B. the drought was serious enough

C. the people had to be helped

D. the famine was terrible enough

5.Hearing the clever answer, people laughed at ______.

A. the old man

B. the official

C. the hungry people

D. the policemen nearby the road

A公司拥有B公司18%的表决权资本；B公司拥有C公司60%的表决权资本；A公司拥有D公司60%的表决权资本，拥有E公司6%的权益性资本；D公司拥有E公司45%的表决权资本。上述公司之间存在关联方关系的有( )。

A．A公司与B公司

B．A公司与C公司

C．A公司与E公司

D．B公司与E公司

电信行业客户服务中心市场大面积启动于（）。

循环喷雾技术

X-连锁高IgM血症的诊断依据是

A．CD8阳性T细胞缺乏
B．CD4阳性T细胞减少
C．T细胞CD40L表达缺陷
D．CD45RO表达缺陷
E．CD20阳性B细胞减少