简述体育市场的功能。

用橡皮圈直接套在牙上，以关闭替牙期上中切牙之间的间隙，会形成（）。

A.间隙关闭加速

B.牙龈外形改善

C.重度牙槽骨破坏

D.橡皮圈易脱落而无法关闭间隙

E.牙齿内陷

前列腺颗粒细胞属于

A．中性粒细胞

B．吞噬细胞

C．肥大细胞

D．鳞状上皮细胞

E．间皮细胞

同学们在学习碱的化学性质时，进行了如图所示的实验

（1）写出甲实验中盐酸和氢氧化钠的反应_________。

（2）乙实验中滴加氢氧化钠溶液后，可观察到的现象是____________ 。

（3）丙实验中观察到试管内有白色沉淀产生。

（4）实验结束后，同学们将甲、乙、丙三个实验的废液倒入同一个干净的废液缸中，最终看到废液浑浊并呈红色。

【提出问题】 废液中含有哪些物质？

【交流讨论】①一定含有的物质：碳酸钙、指示剂、水和_________  （写物质名称）。

②还含有能使废液呈碱性的物质。能使废液呈碱性的物质是什么？同学们有如下猜想。

小云认为：只 有碳酸钠小红认为：只有氢氧化钙小林认为：是氢氧化钠和碳酸钠

【实验设计】小方想用氯化钙溶液来验证小云、小红、小林的猜想。查阅资料获悉氯化钙、氯 化钠溶液呈中性，并设计如下实验。请你将小方的实验设计补充完整。

【反思拓展】 在分析化学反应后所得物质的成分时，除了考虑生成物外还需考虑___________         

     The evidence for harmony may not be obvious in some families. But it seems that four out of five

young people now get on with their parents, which is the opposite of the popularly held image of

unhappy teenagers locked in their room after endless family quarrels.

     An important new study into teenage attitudes surprisingly shows that their family life is more

harmonious than it has ever been in the past."We were surprised by just how positive today's young

people seem to be about their families, "said one member of the research team."They're expected to be

rebellious (叛逆的) and selfish but actually they have other things on their minds; they want a car and

material goods, and they worry about whether school is serving them well. There's more negotiation

(商议) and discussion between parents and children, and children expect to take part in the family

decision-making process. They don't want to rock the boat."

     So it seems that this generation of parents is much more likely than parents of 30 years ago to treat

their children as friends. "My parents are happy to discuss things with me and willing to listen to me,"

says 17yearold Daniel Lazall."I always tell them when I'm going out clubbing. As long as they know what I'm doing, they're fine with it." Susan Crome, who is now 21, agrees."Looking back on the last 10 years,

there was a lot of what you could call negotiation. For example, as long as I'd done all my homework,

I could go out on a Saturday night. But I think my grandparents were a lot stricter with my parents than

that."

     Maybe this positive view of family life should not be unexpected. It is possible that the idea of teenage

rebellion is not rooted in real facts. A researcher comments, "Our surprise that teenagers say they get

along well with their parents comes because of a brief period in our social history when teenagers were

regarded as different beings. But that idea of rebelling and breaking away from their parents really

happened during the 1960s when everyone rebelled. The normal situation throughout history has been a

smooth change from helping out with the family business to taking it over."

1. What is the popular images of teenagers today?

A. They worry about school.

B. They dislike living with their parents.

C. They have to be locked in to avoid troubles.

D. They quarrel a lot with other family members.

2. The study shows that teenagers don't want to________.

A. share family responsibility

B. cause trouble in their families

C. go boating with their family

D. make family decisions

3. Compared with parents of 30 years ago, today's parents________.

A. go to clubs more often with their children

B. are much stricter with their children

C. careless about their children's life

D. give their children more freedom

4. According to the author, teenage rebellion________.

A. may be a false belief

B. is common nowadays

C. existed only in the 1960s

D. resulted from changes in families

腹膨隆，脐内陷提示

A．急性腹膜炎
B．肥胖
C．腹水
D．巨大卵巢囊肿