1．數(shù)詞+單數(shù)名詞.如:20-minute 20分鐘的 It＇s 20-minute walk．步行20分鐘的路程. second-class 二等的 That＇s the second-class room． 那是個二等房間. 500-word 五百字的 This is a 500-word composition． 這是一篇五百字的文章. 【查看更多】

 

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在物理學中，磁場的強弱用磁感應(yīng)強度（用字母B表示，國際單位是特斯拉，符號是T）來表示，磁感線越密的地方，磁場越強，磁感應(yīng)強度B越大.

（1）在圖20中，甲為某磁極附近磁感線的方向和分布的示意圖，由圖可知，該磁極為 ▲ 極，若在l處放置一個小磁針，當小磁針靜止時，其指向應(yīng)是圖乙中的  ▲   .
（2）磁敏電阻阻值的大小隨磁場的強弱變化而變，圖丁是某磁敏電阻R的阻值隨磁感應(yīng)強度B變化的圖象，據(jù)圖線可知，磁敏電阻的阻值隨磁感應(yīng)強度B的增大而▲ ．圖線沒有過坐標原點，說明  ▲  .
（3）王強設(shè)計了一個可以測量該磁敏電阻R的電路如圖丙所示，（其中磁敏電阻所處的磁場未畫出）．將該磁敏電阻R放置在磁場中的位置某處，測出電阻后，利用R—B特性曲線可以讀出相應(yīng)的磁感應(yīng)強度.
①在圖甲磁場中1處，測得的數(shù)據(jù)如圖20表中所示，則該磁敏電阻的測量值為 ▲ Ω. 
②根據(jù)該磁敏電阻的R-B特性曲線可知，1處的磁感應(yīng)強度為   ▲    T.
③在實驗過程中，僅將磁敏電阻從1處移至2處，其它條件不變，那么電流表的示數(shù)
▲   （填“增大”、“減小”或“不變”）.
④依據(jù)上述方法獲得的磁感應(yīng)強度B的測量值與該點實際值存在不小的誤差，為盡可能準確反映空間某點磁場的強弱，你認為在選擇磁敏電阻時應(yīng)注意什么問題？

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按要求寫出下列單詞的適當形式。
1. radio (復(fù)數(shù))______    
3. sun (形容詞)______    
5. better (反義詞)               
7. care (副詞)______         
9. stop (過去分詞)______ 		2. busy (副詞)______    
4. thirty (序數(shù)詞)             
6. write (名詞) ______                                                         
8. begin (現(xiàn)在分詞)______ 
10. dangerous (名詞)______  

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Reading comprehension.
                                                        
        Do you feel a little sleepy after lunch? Well, that's normal. Your body naturally slows down then.
What should you do about it? Don't reach for a coffee! Instead, take a nap. 
        There are many benefits of a daily nap. First of all, you are more efficient after napping. You
remember things better and make fewer mistakes. Also, you can learn things more easily after taking
a nap. A 20-minute
nap can reduce information overload. It can also reduce stress, Finally, a nap may increase your self-
confidence and make you more alert. It may even cheer you up.
         But, there are some simple rules you should follow about taking a nap. First, take a nap in middle
of the day, about eight hours after you wake up, Otherwise, you may disturb your sleep-wake pattern.
Next, a 20~30 minute nap is best. If you sleep longer, you may fall into a deep sleep. After waking from
a deep sleep, you will feel worse. Also, you should set an alarm clock. That way, you can fully relax
during your nap. You won't have to keep looking at the clock and you won't oversleep.
        Now, the next time you feel sleepy after lunch, don't get stressed. Put your head down, close your
eyes, and catch forty winks.
        Choose the best answer from A. B. C or D according to the passage.
1．What is the main idea of this reading?
[     ]
A．Why children take naps.
B．How to sleep deeply.
C．Why napping is good.
D．The problems with napping.
2．According to the reading, what is not a benefit of napping?
[     ]
A．It improves you memory
B．It makes you feel happier.
C．It gives you more self-confidence.
D．It makes you stronger.
3．What is a good rule for taking a nap?
[     ]
A．Use an alarm clock.
B．Nap eight hours after waking up.
C．Sleep for about half an hour.
D．All of the above.
4．What is the best napping schedule?
[     ]
A．Two 60 minute naps per day.
B．One nap each day.
C．Napping only in the evening.
D．Napping only in the morning.
5．Which may occur if an alarm clock is not used?
[     ]
A．You may relax more.
B．You may feel too nervous to relax.
C．You may forget an important meeting
D．You may not reduce your napping time.

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按要求寫單詞。
1. go (第三人稱單數(shù)形式)
2. too (近義詞)
3. comedy (復(fù)數(shù)形式) 
4. fun (形容詞)
5. act (名詞)    
6. nine (序數(shù)詞)
7. movie (復(fù)數(shù)形式) 
8. party (復(fù)數(shù))
9. China (形容詞) 
10. different (反義詞)
11. art (表示人的名詞) 
12. two (同音詞)		 ______________                                             
______________
______________
______________
______________
______________
______________
______________
______________
______________
______________
______________

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【小題1】Those are orange coats.（改為單數(shù)）
____1____ ____2____ orange coat.
【小題2】I go to the school library every Tuesday. （改為一般疑問句）
   3   you go to the school library every Tuesday?
【小題3】Kate lives in a tall building in the middle of the city.  (改為否定句)
Kate   4    ____5____ in a tall building in the middle of the city.
【小題4】The teacher has some books in his hand.  (同義句改寫)
_____6_____ ____7______ some books in the teacher’s hand.
【小題5】The model plane is Nick and Peter’s. (對劃線部分提問)
____8____ is the model plane?
【小題6】There is only one photo on the wall. (對劃線部分提問)
_   9_____ _____10______ _____11______ _____12______ there on the wall?
【小題7】We can read books in the reading room. (對劃線部分提問)
____13_____      14    you _____15_____ in the reading room?
【小題8】She often goes shopping after supper. (就劃線部分提問)
   16         17    she often     18    shopping?
【小題9】We go to school five days a week.
    19        20     do you go to school?

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