____,the compass was first made in China.

解题思路：第一宇宙速度7.9 km/s是指卫星绕地球表面在地球引力的作用下绕地球做圆周运动，了解同步卫星的含义，同步卫星在地球上空固定的高度上，其周期与地球自转周期相同，相对地面静止．

A、第一宇宙速度是近地卫星的环绕速度，也是最大的圆周运动的环绕速度．而同步卫星的轨道半径要大于近地卫星的轨道半径，根据v=

GM
r，可以发现，同步卫星运行的线速度一定小于第一宇宙速度．故A错误；
B、因为同步卫星要和地球自转同步，即ω相同，根据F=
GMm
r2=mω²r，因为ω一定，所以 r 必须固定，故B正确；
C、根据万有引力提供向心力，F=
GMm
r2=mω²r，得：ω=

GM
r3，同步卫星的轨道半径要小于月球的轨道半径，所以同步卫星绕地球运行的角速度比月球绕地球运行的角速度大，故C错误；
D、同步卫星与赤道上的物体具有相同的周期，根据向心加速度的公式：a=
4π2
T2r，同步卫星的轨道半径要大于静止在赤道上的物体的轨道半径，所以同步卫星向心加速度比静止在赤道上的物体的向心加速度大，故D错误．
故选：B．

点评：
本题考点： 人造卫星的加速度、周期和轨道的关系；万有引力定律及其应用．

考点点评： 本题考查了万有引力提供向心力，第一宇宙速度，线速度、角速度与轨道半径的关系，同步卫星的特点．比较两物体的线速度，角速度、周期与半径的关系只要找准相同的物理量就能顺利解决此类题目．

inwented inventor
western
gone
had started
changed
祝你学习进步

指南针说明校正（TO TAKE A FIX）：用指南针的指针对准一个明显的地标（地面标志物）或者显示在地图上的特别的标志.读出指南针刻度盘上的读数.比如,假设你看到一座灯塔,方位角（指针和N重合时）是40度.此时将指南针...

指南针
双语对照
词典结果：
compass points
n.罗经（方位）点( compass point的名词复数 ); 罗经点;
以上结果来自金山词霸
展开更多词典
例句:
1.
The needle on a compass points north.
指南针的指针是指向北的.

A

他认真地研究指南针
studied应该是研究的意思

我觉得这题选E,这个平行结构,前面两句都是Mike might not have...,Lewis and Isaac might not have.,所以最后这句的结构应该要和前两句一样.
个人意见,仅供参考

C which 代指前文出现的compass
that 一般不可接在介词后,除了in that ,for that 等固定用法.

答案是：A.It was from the teacher that
首先是 hear of something from somebody 的搭配,由此可排除B,D.
然后it is .that ...的由it 开头引导的从句,也是固定搭配,因此选A.

devices

不是的,最后面的是名词,是指南针的意思吧.
我对这句话的理解是一个副词后面有一个形容词没什么问题呀

小题1:D
小题2:B
小题3:B

由内部罗盘导航要靠地球的磁场.

你的句子是为了突出指南针在航海事业上面的重要吗?你的句子上是没问题,虽在有否定的意思的时候用or 连接较为直观些.（lewis or clark might .)但你每个句子都是单独的成分,所以用and 也可以.

小题1:B
小题2:B
小题3:B


小题1:全文都在介绍李春怎样建造赵州桥。
小题2:第三段主要介绍赵州桥的长度、拱洞的数目和跨度以及结构的科学性和美观性。
小题3:根据信息词“transport heavy rocks and other materials”可以判断出该词的意思是“运输工具”。

选D
The compass was first made in China,which is to us all.
这是一个非限制性定语从局 which代指的是 the compass was first made in China
而 as 也可以做为关系词 与which的功能是一样的
除此之外 as 还可以位于句首 可以翻译成 正如我们所知道的,指南针最早出现在中国

A、所有地球的同步卫星都位于赤道的上空，在相同的轨道上运行．故A错误．
B、同步卫星的周期与地球的周期相同，根据ω=
2π
T 知，同步卫星的角速度相等．故B正确．
C、根据万有引力提供向心力 G
Mm
r 2 =m
v 2
r 知，v=

GM
r ，轨道半径越大，线速度越小，7.9km/h是贴近地球表面运行的速度，所以同步卫星的速度小于7.9km/h．故C错误．
D、同步卫星的角速度与地球自转的角速度相等，根据a=rω ² 得，同步卫星的向心加速度大于赤道上物体的向心加速度．故D错误．
故选B．

我闲来无聊,就回答一下吧!
1.指南针永远指向南方.point to固定词组,指向.
2.当你过马路,你应当先看马路左边.look to left向左边看
3.科学家下个月将会给我们演讲是真的吗?用is it true逐句一般将来时,从句一般现在式.
4.他们是好朋友,对于他们熟知彼此就没什么好奇怪的了.that is why这个用法知道不,这里一样的用法.（具体啥从句我不是很确定,就不说了,记住这个用法就好）
5.在过去的400年增长很快.in the past XX yesrs在过去XX年,固定用法啊.这里通常考你in the past XX yesrs要用现在完成时态,注意这点.
6.你能告诉我他什么时候回来吗?is coming 是现在时态表示将来含义.有很多这种词,比如go,die.
7.是left吧?你今早走的时候雨下得很大吗?从意思上肯定是过去式啊,有什么疑问吗?
8.他们照父亲所说的做.这里的as是正如,按照的意思.
9.她是一个很好的女孩来一起共事.to work with与什么共事,你想怎么用?
10.她花了两个小时在实验上面.固定搭配啊It takes sb+一段时间或者金钱+to do sth.
分你不用多给了,我是无聊啊答着玩的~

您好
D
D
回答完毕
：）祝您愉快

To set up a clear aim in your life is of the utmost importance.In your childhood,parents and teachers are able to lead you to the right direction,and you could live well without aims.However,as you grow up,nobody would help you when facing different choices.What to do and how to live depend on what you want.That's your aim in the life.As we all know,a boat struggling the wind and waves can't reach the greatbeyond without a compass.Similarly,you can't achieve the success without a aim in your life.

A

解题思路：同步卫星的特点：定周期（24h），顶轨道（赤道上方），定高度，定速率．而地球的第一宇宙速度是卫星贴近地球表面做匀速圆周运动的速度．由运动情景可知r越大，v越小，可知同步卫星的速度小于第一宇宙速度．要比较同步卫星的向心加速度和静止在赤道上物体的向心加速度大小，可根据公式：a=rω²，ω相同，半径大的向心加速度大．

ABC、三颗星属于地球同步卫星，所以它们的运动速度大小、周期、离地心距离相等，其环绕速度约为3.1km/s，故A对B、C错，
D、同步卫星与赤道上物体绕地球运动的角速度相等，由a=rω²可知同步卫星的向心加速度大，故D错．
故选：A

点评：
本题考点： 同步卫星．

考点点评： 解决本题的关键要理解同步卫星的特点和第一宇宙速度的概念．要注意赤道上物体随地球一起自转所需的向心力不是由万有引力提供

生活没有了目标,就像航行没有了方向……

1.D 主语从句,且主句不缺少任何成分,所以用that引导（类似于宾语从句）.
2.C “sth need doing 某事需要被做”,用主动表示被动.
3.B prefer doing sth to doing sth=prefer to do sth rather than do sth
4.A have something/nothing to do with sth 和某事有/没有关系
5.A meet one's demand 满足某人的需求,再用其被动结构.

这样理解看看：en-有使...置于之中的意思,compass是指南针,把指南针置于圆盘之中,就是包围起来咯.

A man does not have a clear goal, is like a ship without a compassThe success of a Harvard famous: "the goal is not everything, but like a ship sailing to compass, if a ship sailing ship without a compass, it will not know in what direction, do not know what time of arrival."As interest and preference can induce talent, diligence and will be able to cultivate the talents, the ideal and the goal to encourage talents."The goal of life is sober agent, planning is the life of the accelerator." Objective the meaning and purpose of human life.A foreign, devoted to the study of "success" research institutions, in one hundred young subjects of the investigation. The study lasted for decades, until the year be in high and vigorous spirits of young people to become fifty or sixty years old frail old man. The results showed that: only one of them is very rich, in addition to the five individual economic security, the remaining ninety-four people are not very good, can be said to be the loser. And that the vast majority of people encounter later in reduced circumstances reasons, not when they were young don't work hard, but their young when not set clear goals.With the goal, people will concentrate on the pursuit of happiness, not to avoid pain. Objective to let everyone morning get up in the morning, there is the passion of the struggle.Clear goals in life is a matter of importance, in other words, is your life ambition, but ambition sounds as a controllable beyond the scope of personal things, and life goals are, if willing to devote energy to do, it may be. Therefore, for individuals, this is what life really want? What do you really want to do? This is your goal, to each of these goals in one sentence. If some of these goals is reaching another step, then remove it from the list, because it is not your goal in life. The target is your life ship compass, grasp it can not detours.Dendrolimus punctatus in pine netting to the nest, this is their common form of collective spin. When dusk, they sally forth in full strength to climb trees, lined up, to eat those juicy pine needle. The caterpillars in the walk, there is a kind of follow each other's instinct, head of walking in front, followed by a caterpillar, orderly, serpentine. Walk in front of the head, while crawling, while continuing to spit out a silk. Wherever it went, silk spit where. To go in front of the pine caterpillar is laying on the road, no matter how far out to the troops, how long does it go, are able to return along the paved road, and not lose the direction.French entomologist Farber, according to the characteristics of Dendrolimus did an experiment. He put a team caterpillar into a large pot, forming a circle, the caterpillar climbed up the pot edge, Farber a pot around the wire off, leaving only the flower pots on the edge of the wire, and put some pine flower pot in central. The pine caterpillar began around the pot edge, receive only blindly go, another circle repeatedly, they think that as long as the Silk Road in, will not lose the. So repeatedly gone days night, pine caterpillars are simply did not know can help food from his a few steps away, eventually because of hunger, fatigue and die.Many people like the pine caterpillar, blindly machinery to spend every day. They are in accordance with the established pattern, every unsuspectingly to live. If asked them why, they might say: "everyone is not the way to live?"This is no goal state of human existence, their life is like losing compass ships, confused, fluttering, not only would never reach the other shore, dangerous and always have a dead, buried in the bottom of the sea.Are important objectives for each person's success, clear goals is like life, the ship's compass. The ship out to sea, with the compass is the first requirement, so the life goal is the first element, and a first step on the road of life. Because the goal is the motive, goal is the direction, only towards the goals set forward, in order to achieve rich, successful life大热天写一篇英文不容易,求采纳!

compass in China?A.the

un是通过.
through a point halfway 这里你应该这样分解这句话去理解
run "from the center of the watch" "through a point" "halfway between the hour-hand and number one"
一条线通过 表的中心 和 一点,那这一点是哪一点呢,就是时针和12点的连线的中点.那两个点就决定了这样一条线,这条线指的就是南方.
2.想象有一条线,这条线通过了表的中心和时针与12点连线的中点.


再完整一点说明好了.这里实际上是一种利用手表指南的方式.将时针对准太阳,那么时针与12点连线的中点与表的中心连线指的就是南方.

这个是约定俗成的 就像cloth 一样 加es后也是读s 我问过我们外教 他就是这么讲的 她们从小就这样读 因为大家都这样读

答案D
as可以用于句首引导非限制性定语从句,先行词是后面的整个句子.

A aim is to living what a compass to sailing.
目标对于生活就像指南针对于航行一样.
固定句型：A is to B what C is to D. A之于B如同 C之于D.
希望对你有帮助：）

B.
It is known that the compass was first invented in China.
这里是一个主语从句,it做形式上的主语,真正的主语是that the compass was first invented in China这个从句.由于这是一个主语从句,所以that不能省略.
A选项缺少that C选项 语态以及引导词不符 D选项如果改为AS KNOWN TO ALL THAT 才对

我觉得这题选E,这个平行结构,前面两句都是Mike might not have...,Lewis and Isaac might not have.,所以最后这句的结构应该要和前两句一样.
个人意见,仅供参考

一、1,fake是虚伪的,伪造的,false是错误的,扭曲事实的.两者有天壤之别.eg.Your answer is false.或This VCD is fake.答案只能是错误的不能是虚伪的；而VCD只能是盗版的不能是错误的.
2,border边境,cpmpass指南针,bound有国度或回合(比赛)的含义
3,include包含(具体),包含你我可以说include you and me,contain指容器中装了什么,杯子装了水.Cup contains water.embody（抽象）体现,如文章包含了什么含义等.involve涉及人或事物.
4,decorate装饰,为...做室内装修,点缀；deck是甲板或装饰.
5,diversion多样化,amusement好笑,滑稽,entertainment娱乐.
6,三者都有设计的意思,design一般是指建筑的图纸设计,室内设计等.
7,internal是内在的,interior是指次要的.
8,decide是个人决定做出的选择,determine是坚定的信仰.
9,invade和intrude都有入侵的意思,但intrude还有思想上入侵的意思.
10,deed行为,contract合同
二、1,judgement是指作出的裁判而justice指正义或法官.如：the judgement made by justice is correct.法官做出的裁决是正确的.
2,country是广义的农村,农村的统称,而countryside一般强调田园风光.
三、内容好多,还要造句子太复杂了,有时间一一造句.先就这样吧.

只是对于我们来说就像罗盘对航船一样重要.一艘船要靠罗盘来安全的驶过一片未知的海域.同样地,知识带给我们向更好的生活努力前行的力量.有了知识,我们可以发明有用的机器；我们可以创造令人欣赏的艺术,比如作画,雕刻,音乐等等；我们可以制作衣服,家具,汽车,航天飞行器以及类似的种种.是知识让我们人类能过活一个方便且多彩的生活.简而言之,我们掌握越多的知识,我们就可以变的更睿智.
倒数第二句有用到it is···that 的强调句~

getting lost
avoid doing sth 避免做某事

MP3.When you feel bored ,you can listen to music to entertainment so that you can enjoy yourself.
BOOKs.We all know that book is the knowledge of in which you can soar freely.
Compass.You may easily disoriented in the wild without a compass.You can get a right direction with a compass.
Arthicles .这个单词是不是您拼错了呢?
Documents.Portable document may help you get a right decision when you feel puzzled.

compasses圆规 （两只脚）