题目内容

以下有关动物激素和植物激素的叙述中,错误的是(          )
A.都是由专门器官分泌的B.对新陈代谢、生长发育都有重要调节作用
C.在生物体内的含量都极少D.都是由活细胞产生的
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What do you think of stress? Is it a good thing or a bad thing?
Most of the students think stress can do harm (伤害)   46  them in some ways. There’s a story about a teenager in a middle school. He even   47  his study because of the stress from school and family. We also usually   48  that someone turns to psychological doctors because of heavy working stress. There is no doubt (疑问) that some people think stress is a dangerous wolf.
On the other hand, other people argue that stress is not a bad thing. They   49  stress can produce momentum (动力)in the end. For them, right attitude and action can reduce (减少) stress and make it   50 . When I was a child, my mom always pushed me to study hard. She wished I could go to an ideal   51  for further education. I experienced stress for the first time. To a poor family, I deeply knew   52   was not easy for us, and everything my mom did to me was just to hope I could live a better life in the future.   53  the saying goes, “No pains, no gains.” So I did what my mom expected because I didn’t want to let her down. At last, I did measure up (达到标准)to my mom’s expectation and go to college   54 . Thanks to my mom’s push! Thanks to the stress! In this way, I don’t think stress is a bad thing.
Overall, stress is not a bad thing in   55 . The key is how we deal with it.
【小题1】
A.forB.inC.toD.of
【小题2】
A.began withB.gave outC.gave upD.gave away
【小题3】
A.wonderB.decideC.lookD.hear
【小题4】
A.doubtB.believeC.disagreeD.forget
【小题5】
A.usefulB.difficultC.strangeD.terrible
【小题6】
A.companyB.collegeC.factoryD.village
【小题7】
A.lifeB.sportC.opinionD.silence
【小题8】
A.ThenB.ButC.AsD.Or
【小题9】
A.quietlyB.wildlyC.speciallyD.successfully
【小题10】
A.himselfB.myselfC.itselfD.yourself
Mobile phone (手机)has become a problem for middle schools. Some middle schools in Australia have banned (禁止) students from carrying mobile phones during school hours.
Mobile phone use among children has become a problem for the schools this year. Several children have got mobile phones as Christmas presents, and more students want them.
Mary Bluett, an official(官员), said mobile phone use is a distraction(分心) to students during school hours and it also gives teachers so much trouble in their classrooms. Teachers were also saying that sometimes students might use phone messages to cheat during exams.
She said some schools had tried to ban mobile phones. Some parents felt unhappy, because they couldn’t get in touch with their children.
Many teachers said students should not have mobile phones at school, but if there was a good reason, they could leave their phones at school office. They also said there were many reasons why the students should not have mobile phones at school; they were easy to lose and were a distraction from studies.
Many people say that they understand why parents would like their children to have phones, but they think schools should let the students know when they can use their mobile phones.
【小题1】Some middle schools in Australia have banned students from carrying mobile phones ____.
A.because they are studentsB.when they are free
C.when they are at schoolD.because they are children
【小题2】We know from the passage that some children get mobile phones from _______.
A.the makers and sellers
B.the passers-by and strangers
C.their parents and friends
D.some mobile phone users
【小题3】What does the word “cheat” mean in the passage in Chinese?
A.聊天B.核对C.查询D.作弊
【小题4】 Some parents felt unhappy because they couldn’t________ during school hours.
A.use their mobile phones
B.leave their mobile phones at school office
C.help the teachers with their work
D.get in touch with their children
【小题5】The passage tells us that_______.
A.students shouldn’t have mobile phones at school except for some special reasons
B.it is impossible to ban students from using mobile phone at school
C.some parents felt unhappy because they couldn’t Use their phones at school
D.parents should teach their children how to use mobile phones during school hours
小刚家准备建一栋新房,爸爸买了一堆材料相同的石子,小刚选取一块石子在实验室测它的密度.
他先将托盘天平放在水平桌面上,调节托盘天平平衡时,发现指针停在分度盘的右侧,要使天平平衡,应将横梁右端的平衡螺母向   (左/右)移动;当他用天平测物体质量时,发现指针偏向分度盘的左侧,这时应该在天平右盘中      (增加/减少)砝码;
测小石子的密度,主要实验步骤是: A.用量筒测出小矿石的体积;B.将小矿石从水中取出,立即放在已调节平衡的天平盘上,加减砝码和调节游码,测出小矿石的质量;C.再用密度计算公式求出小石子的密度.请你评估:这一实验过程测算出的密度结果______(选填“偏大”、 “偏小”或“准确”),原因是_______________________.

刚按图甲所示的方法测石子的质量,请指出操作中的三个错误:
                                                      
                                                      
                                                      
纠正错误后继续实验,当盘中所加砝码和游码位置如图19乙所示时天平平衡,则此石子的质量为      g.在量筒内装有一定量的水,该石子放入前、后的情况如图19丙所示,则石子的体积是       cm3,此石子的密度是           kg/m3

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