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问题 选择题

物质分类的依据通常是根据它的组成和性质，下列物质的分类中，只考虑组成的是（　　）

A．硫酸钠是钠盐、硫酸盐、正盐

B．二氧化硫是氧化物、酸酐、有漂白性物质

C．氢氧化钠是一元碱、易溶性碱、强碱

D．碳酸氢钠是钠盐、酸式盐、易分解的盐

答案

A、是根据组成来得出硫酸钠在溶液中的离子构成，进而进行所属类别的判断的，故A正确；

B、该种分类的依据是根据二氧化硫的性质，故B错误；

C、该种分类的依据是根据氢氧化钠的组成和性质，故C错误；

D、该种分类的依据是根据氢氧化钠的组成和性质，故D错误．

故选A．

填空题

When I was growing up, I was embarrassed to be seen with my father. He (1) severely crippled and very short, and when we would walk together, his hand on my arm (2) balance, people would stare. I would inwardly be afraid (3) squirm at the unwanted attention. If he ever noticed or was bothered, he never let (4) .
It was difficult to coordinate (5) steps - his halting, mine impatient - and because of that, we didn’t say much as we went along. But as we started out, he always said, "You (6) the pace. I will try to adjust to you. "
Our usual walk was to or (7) the subway, which was how he got to (8) . He went to work sick, and (9) nasty weather. He almost never missed a day, and would (10) it to the office even if (11) could not: a matter of pride!
He never talked about himself as an object of pity, (12) did he show any envy of the more fortunate or able. What he looked for in others was a "good heart", and if he found one, the owner was good enough for him.
Now that I am older, I believe that is a proper standard (13) which to judge people, even though I still don’t know precisely (14) a "good heart" is. But I know the times I don’t have one myself.
He has (15) gone many years now, but I think (16) him often. I wonder if he sensed my reluctance to be seen with him during our (17) . If he did, I am (18) I never told him how sorry I was, how unworthy I was, how I regretted it. I think of him when I complain about trifles, when I am (19) of another’s good fortune, when I don’t have a "good heart".
At such times I put my hand on his arm to regain my (20) , and say, "You set the pace, I will try to adjust to you.\
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单项选择题

左侧卧位可使腹痛减轻提示何种疾病

A．十二指肠淤滞症

B．胰体癌

C．反流性食管炎

D．胃粘膜脱垂

E．胃溃疡
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