方法:1.在动词后直接加ed. 如:clean-cleaned 查看更多

 

题目列表(包括答案和解析)

完成家谱(family tree)。

小词典:同学们,你们注意看看这些表家庭成员的单词,多数都是以-er结尾。-er这个结尾常表示人。如上文的mother,father,sister,brother等。除此之外,还有一种是在动词后加-er构成名词的,在语法上,我们称之为单词后缀。如动词teach是表示教、讲授,加上后缀-er,那么教书的人就是老师(teacher)了。另外,后缀-or也可以表人物,如演员actor。此类的词还有很多,以后慢慢给大家介绍。

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在物理学中,磁场的强弱用磁感应强度(用字母B表示,国际单位是特斯拉,符号是T)来表示,磁感线越密的地方,磁场越强,磁感应强度B越大.

(1)在图20中,甲为某磁极附近磁感线的方向和分布的示意图,由图可知,该磁极为 ▲ 极,若在l处放置一个小磁针,当小磁针静止时,其指向应是图乙中的  ▲   .
(2)磁敏电阻阻值的大小随磁场的强弱变化而变,图丁是某磁敏电阻R的阻值随磁感应强度B变化的图象,据图线可知,磁敏电阻的阻值随磁感应强度B的增大而▲ .图线没有过坐标原点,说明  ▲  .
(3)王强设计了一个可以测量该磁敏电阻R的电路如图丙所示,(其中磁敏电阻所处的磁场未画出).将该磁敏电阻R放置在磁场中的位置某处,测出电阻后,利用R—B特性曲线可以读出相应的磁感应强度.
①在图甲磁场中1处,测得的数据如图20表中所示,则该磁敏电阻的测量值为 ▲ Ω. 
②根据该磁敏电阻的R-B特性曲线可知,1处的磁感应强度为   ▲    T.
③在实验过程中,仅将磁敏电阻从1处移至2处,其它条件不变,那么电流表的示数
▲   (填“增大”、“减小”或“不变”).
④依据上述方法获得的磁感应强度B的测量值与该点实际值存在不小的误差,为尽可能准确反映空间某点磁场的强弱,你认为在选择磁敏电阻时应注意什么问题?

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动词运用(共10小题。计10分)
用括号内所给动词的适当形式完成下面短文,必要时可加助动词。(请将各小题的答案写在短文后相应的横线上。)
Mr and Mrs Smith were giving a dinner party with 20 visitors seated around a table. Their talk was about who 【小题1】      (have) more self-control(自我控制力 ),men or women.
Suddenly they saw a strange expression ( 表情 ) 【小题2】      (come) across Mrs Smith's face. She said something to the servant(仆人) standing behind her without 【小题3】      (turn) around. The servant quickly put a glass of milk outside the open door.
One of the men said,  "I want to know what self-control everyone 【小题4】     (have). While I 【小题5】      (count) from 1 to 300, none of you can move at all. If you do,  you【小题6】      (pay) 50. "
The people sat like rocks while the man counted. When he reached 280, a large snake(蛇)【小题7】       (see) moving slowly from the table to the glass of milk.
Mr Smith said,  "You 【小题8】     just       (show) us an example of self-control,  but how did you know there 【小题9】     (be) a snake in the room?"
"I 【小题10】       (not,  know) it was,  but I knew the milk was for the snake,  "the man answered.
"It was lying right on my feet, " said Mrs Smith.

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(11分)下图甲、乙分别表示我国医学工作者自主研制SARS灭活疫苗过程中,某志愿者接种疫苗后两周内体温和抗体浓度的变化。请据图回答下列问题

(1)注射疫苗后,志愿者出现轻度发热现象,调节机体产热的激素主要有          
                      ,维持体温恒定的调节方式是                      调节,
体温调节中枢是______________。
(2)若该志愿者注射疫苗后的第15天感染SARS病毒,请在乙图中画出其体内抗体变化曲线。抗体的本质是_________,由_____________直接产生,抗体合成及分泌的途径是________________________________________________________(2分) 。
(3)研究发现SARS病毒的增殖需要逆转录酶,说明SARS病毒的遗传物质是       
;从遗传物质分析,研制SARS疫苗困难的主要原因是                             

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动词运用(共10小题。计10分)

    用括号内所给动词的适当形式完成下面短文,必要时可加助动词。(请将各小题的答案写在短文后相应的横线上。)

Mr and Mrs Smith were giving a dinner party with 20 visitors seated around a table. Their talk was about who  1.       (have) more self-control(自我控制力 ),men or women.

Suddenly they saw a strange expression ( 表情 )  2.       (come) across Mrs Smith's face. She said something to the servant(仆人) standing behind her without 3.       (turn) around. The servant quickly put a glass of milk outside the open door.

One of the men said,  "I want to know what self-control everyone 4.      (have). While I 5.       (count) from 1 to 300, none of you can move at all. If you do,  you6.       (pay) 50. "

The people sat like rocks while the man counted. When he reached 280, a large snake(蛇)7.        (see) moving slowly from the table to the glass of milk.

Mr Smith said,  "You 8.      just       (show) us an example of self-control,  but how did you know there  9.      (be) a snake in the room?"

"I 10.        (not,  know) it was,  but I knew the milk was for the snake,  "the man answered.

"It was lying right on my feet, " said Mrs Smith.

 

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