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在人类认识地球及其运动的历史上，托勒密提出了说，哥白尼则提出了说。

对待公有制经济，必须毫不动摇地(    )

写出中动词的过去式。

go buy   eat  take ride

阅读理解

People are always trying to live a healthy life. You might have read so much on this topic. The following ideas may sound strange, but they can really help you.

Exercise when you are tired.

After a long and tiring day of study, exercising might not sound like a good idea, but it should. In fact, physical activities can provide you with the missing energy. Research shows that exercising for just 30 minutes can make you feel good!

Write by hand to help the brain be active.

Although writing something using a computer is faster, it is much better to remember the whole thing by writing it down by hand. When you read a handwritten text, naturally it's easier for your brains to remember the information.

Spare more time for yourself.

By sparing the time for yourself and just being alone for a while, you can have a chance to think and get to know yourself better. And you won't behave impulsively (冲动地).

Drink hot drinks on a hot day.

What cools more on a hot summer morning, cold water or hot water? The study shows that the hot water does make people feel cooler. When you are drinking something hot, the body will feel the change in temperature and increase the perspiration(流汗), which helps you cool down!

阅读下文，回答问题

    我的脸由于困窘和羞愧一下子涨得通红。只有这时候我才意识到，老师误解了我的笑声，以为我的笑不怀好意。幸亏她没有容我解释，不然的话，同学们听见我说自己三年前就发现了进化论，还不笑塌房顶！/不过，被轰出教室，站在外面，我倒想出了一条自我安慰的理由，我明白了——世界上重大的发明与发现，有时还面临着受到驱逐和迫害的风险。

2017年5月9日，中国科学院发布了113号、115号、117号及118号四种元素的中文名称，其中一种元素在元素周期表中的信息如图所示，下列有关该元素的说法正确的是（   ）

近来，对“躺平”的不同理解引发各种热议，有人把“躺平”等同于不思进取，有人认为“躺平”是在面对现实困难时给予自己的短暂喘息，是人们在面对生活、工作各方面的现实压力而做出的自我治疗。对“躺平”的不同理解表明（   ）

①矛盾是对立统一的，要在斗争中把握同一

②价值观是对社会存在反映，不以人的意志为转移

③不思进取的“躺平”对社会对人生会产生负面影响

④自我疗伤的“躺平”对人的生理活动可能会起积极作用

分解因式 的结果是.

如图，EF∥AD，∠1=∠2，∠BAC=80°．将求∠AGD的过程填写完整．

因为EF∥AD，

所以∠2= （ ），

又因为∠1=∠2，

所以∠1=∠3（ ），

所以AB∥（ ），

所以∠BAC+ =180°（ ），

因为∠BAC=80°，

所以∠AGD= ．

比较距离时，起点必须在一条线上。

阅读理解

We often find that weekends and holidays feel so short while classes and work feel so long. Actually, though, we know that this is not true. But we still wonder where that strange feeling comes from. In fact, this is one of the ways that we're tricked by time, according to the website All That Is Interesting. The website lists several wrong impressions we often have about time. Let's have a look.

First of all, emotions affect our time-keeping abilities. Negative emotions, especially anxiety and boredom, make time seem longer because they make us concentrate more on the passage of time. However, when we are enjoying ourselves, we pay more attention to what we are doing and are likely to lose feeling of time.

Here is another example. In 2007, a group of scientists carried out a test. In the test, people fell 50 meters into a safety net and were then asked about their experience. Although the experience took shorter than 3 seconds, the people thought it was much longer than it actually was. This is because of the way our bodies reply to danger, according to the scientists. Our bodies produce a chemical called adrenaline (肾上腺素) when we are faced with danger. It allows us to concentrate better so that we can stay alive. As a result, we are able to remember far more details over a short period of time, which makes it seem like time is going more slowly.

Another situation when we make mistakes about time is when we take afternoon naps (午觉). Have you ever had trouble telling what time it is after a long nap? That's because the best amount of time for a nap is 20 minutes. After 20 minutes, you enter a new stage of sleep called slow-wave sleep. If you wake up mid-way in this stage, it will take a while before you can correctly feel time again.

Yes, time can be mysterious and there is no way to control it. So, perhaps the best thing to do is to make good use of every minute.

如图，正方形OABC的两边OA、OC分別在x轴、y轴上，点D(5，3)在边AB上，以C为中心，把△CDB旋转90°，则旋转后点D的对应点D′的坐标是（   ）

下列有关对人体消化和吸收营养的描述中，不正确的是（　　）

如图，在 的方格纸中，每个小方格都是边长为1的正方形，点 、 、 是格点，则图中扇形 中阴影部分的面积是．

 

函数 的部分图象可能是（    ）

如图示意某区域河流水系和年降水量分布。读图，完成以下小题。

你在家中做过哪些家务活？

2021年1月22日，京哈高铁全线贯通。这是我国“八纵八横”高速铁路网京哈一京港澳通道的重要组成部分。据下图，回答问题。

一个布袋内只装有1个黑球和2个白球,这些球除颜色不同外其余都相同,随机摸出一个球后放回搅匀,再随机摸出一个球,则两次摸出的球都是黑球的概率是(    )

已知x= ，y= ，求代数式（x+y）²﹣（x﹣y）²的值．