__________A.exhaustB.exerciseC.examD.exact
__________
A.exhaust
B.exercise
C.exam
D.exact
B.exercise
C.exam
D.exact
参考解析
解析：
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当幼苗的乳叶刚长出两片真叶①的时候，就可以移植②栽种了。先挖好五寸左右的小坑，再在坑内施放些③鸡粪、猪粪作基肥。④幼苗不要种得太深，⑤因为幼苗种得太深了不透风，会影响根系的生长，碰到下雨天，还⑥容易烂根。也不能太浅，⑦如果种得太浅了，遭到干旱天容易晒死。深度⑧最好在1～2厘米左右。幼苗移植后⑨的最初三天，傍晚都要⑩给幼苗浇水。所以我家种的向日葵是百分之百成活。 上段文字中，有一句话的表述偏离了文段的陈述中心，请找出来，并加以修改。原文：__________________________________________________________________________________________________________________________________ 修改：________________________________________________________________________________________________________
假如你把一根大头针戳进气球，要过多久气球才会爆裂呢 不需要很久，而且这个时间可以利用高速摄像来测定。不管怎样，橡胶在压力之下裂开，总是要耗费“一点儿”时间的。然而，假定你取一个分子，它只有十亿分之四英寸大，对它完成相当于把一根针戳进气球的动作，那么这个分子要隔多久才会断裂呢 这个时间要比气球爆裂短得多，然而科学家现在照样能测出来。 一个分子是由一团原子组成的。当这些原子互相靠得足够近，由于它们外层区域的微小电子相互交叠在一起，因而使这些原子粘合在一起了。这种电子的交叠形成了一种稳定状态，倾向于保持不变。为了保持这种状态，原子必须继续保持紧密相连，这就形成了所谓的“化学键”。 形成一个化学键的两个原子并不是保持静止不动的。在绝对零度(等于一273℃)以上的任何温度下，原子总是倾向于以随机的方式随意运动。不过，当它们被化学键绑在一起后，就不能再自由运动，但可以这么说。它们仍不断地尝试作自由运动。被化学键绑在一起的两个原子可能会作相互分离的运动，但是化学键会把它们拉回到一起来。它们会再作分离运动，但又被拉回，如此往复。因此．原子就在自己的位置上振动。 化学键活像一个小弹簧，原子相互分离得越远，化学键施加的拉力就越强。然而，如果由于某种缘故，原子的分离运动超过了一个临界值，化学键就会紧张过度，像一根弹簧那样，出现断裂。这时，分子断裂，而原子获释。随着温度升高，原子会逐渐远离，超过化学键的束缚。如果温度升得足够高，分子肯定会断裂。同样，如果注入其他形式的能 量，分子也会趋于断裂。现在的问题是一旦注入足够的能量，分子断裂开的时间有多长。 研究人员发现，一个化学键从受损到断裂所需的时间是2．05×10-17秒。光线以每秒186 262英里的速度运动，这是我们宇宙中能够达到的最快速度。如果一束极快的激光脉冲打 在分子上，在化学键断裂以前，这束光也只能离开四百分之一英寸。 从第一段文意看，对“总是要耗费‘一点儿’时间的”理解，正确的一项是（ ）A.这句话意在强调气球爆裂时间的漫长B.这句话意在强调气球爆裂时间的极短C.这句话意在强调气球爆裂时间相对较长 D.这句话意在强调气球爆裂时间相对较短
Bob said he wouldn′t go to the party as he was busy,but he went there__________A.after allB.above allC.at allD.in all
Enough sleep is important to health.The amount of sleep（21）depends on the age of the per-son and the conditions in which sleep（22）.The young may need more sleep than the old,hut（23）eight hours are enough for the health of grown-ups.Some can do with less than this amount?but（24）may need more.Every person knows his own need.It is then a matter of how to（25）it.Sleep should be always enough to make one relaxed(松弛)and ready for（26）work.Fresh air is（27）to sound sleep(酣睡).It is not（28）reason for some people to insist that?it is practical to sleep in the open air.（29）a person can keep himself warm,out-of-door sleeping?probably gives the body（30）complete relaxation.Ability to sleep is largely a habit.The conditions refen-ed to only lead to sleep.Out-of-door（31）,a good habit of regular drinking and the avoidance of late eating and（32）are all helpful?to sound sleep.Such factors are largely within the（33）of any person.A bath at（34）,neither?hot nor cold but of body temperature,may be helpful to sleep.Sleeping pills should never be taken?except when suggested by（35）.第（24）题选A.childrenB.womenC.othersD.few
Moods,say the experts,are feelings that are likely to become fixed,having effects on one′s outlook（way of looking at things）for hours,days or even weeks.That′s great if your mood is a pleasant one,but a problem if you are sad,anxious,angry or simply lonely.Perhaps the best way to deal with such moods is to talk them out;sometimes,though,there is no one to listen.Modern pharmacology（药物学）offers a lot tranquilizers（镇定剂）and anti-anxiety drugs.What many people don′t realize,however,is that scientists have discovered the effectiveness of several non-drug methods to make you free from an unwanted mood.These can be just as useful as drugs,and have the added benefit of being nonpoisonous.So next time you feel out of sorts,don′t head for the drug store--try the following method.Of all the mood-changing self-help techniques,aerobic exercise seems to be the best cure for a bad mood."If you could keep the exercise,you′d be in high spirits,"says Kathryn Lance,author of Running for Health and Beauty.Researchers have explained biochemical and various other changes that make exercise compare favorably to drugs as mood-raiser.Physical work such as housework,however,does little.The key is aerobic exercise--running,cycling,walking,swimming,or other repetitive and sustained activities that increase the heart rate and circulation（循环）,and improve the body′s use of oxygen.Do them for at least 20 minutes a time,three to five times a week.What is the main subject of the passage?A.How to beat a bad mood.B.How to talk bad moods out.C.How to do physical exercises.D.How to do aerobic exercise.