注射相应疫苗可以预防黄热病，注射的疫苗和获得的免疫类型分别属于（  ）

    The evidence for harmony may not be obvious in some families. But it seems that four out of five young people now get on well 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 had 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 17-year-old 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 me.” 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(反抗) 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 only happened during that one time in 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. ”

 在“验证凸透镜成像规律”实验中，某小组同学利用焦距10厘米的凸透镜，高为3厘米的发光体，光屏和光具座进行实验，将测得的物距u、像距v以及所成像的高L_像分别记录在下表中，在验证得到凸透镜成像的初步规律后，为了进一步研究，他们进行适量的运算，将结果分别记录在下表的后两列中．

与植物细胞相比，草履虫缺少的结构是（　　）

①细胞膜   ②细胞壁   ③叶绿体   ④细胞质   ⑤细胞核   ⑥液泡．

阅读下面文言文，完成下列小题。

蛛与蚕

       蛛与蚕曰：“尔饱食终日以至于老，口吐经纬，黄口灿然，固之自裹。蚕妇操汝投于沸汤，抽为长丝，乃丧厥^①躯。然则其巧也，适以自杀，不亦愚乎！”蚕答蛛曰：“我固自杀。我所吐者，遂为文章^②，天子衮^③龙，百官绂^④绣，孰非我为？汝乃枵腹^⑤而营，口吐经纬，织成网罗，坐伺其间，蚊虻蜂蝶之见过者无不杀之，而以自饱。巧则巧矣，何其忍也！”蛛曰：“为人谋则为汝自谋，宁为我！”

噫，世之为蚕不为蛛者寡矣夫！

     注释：①厥：代词，义同“其”。②文章：带花纹的织品。③衮：读“ɡǔn”。④绂（fú）：古代系官印的丝带。⑤枵（xiāo）腹：空腹。