在2、19、25、57、83、100中,奇数有______,质数有______,

题型:填空题

问题:

在2、19、25、57、83、100中,奇数有______,质数有______,合数有______.

考点:奇数,偶数
题型:填空题

工业生产中用蒸馏法来提高酒精度,其实验装置如图所示,先给含水较多的酒精加热使它汽化,把蒸气引出,再经过冷凝管(冷凝管是双层玻璃管,冷却剂从管口1流入,管口2流出)冷却液化成纯度较高的酒精溶液,这种方法的依据是(  )

A.水的沸点比酒精高

B.水的沸点比酒精低

C.水的比热容比酒精大

D.水的密度比酒精大

题型:填空题

写出与以下字意思相反的字。

黑——(  )  上——(  )  出——(  )  大——(  )

有——(  )  关——(  )  短——(  )  上——(  )

题型:填空题

信息匹配

阅读下列应用文及相关信息,并按照要求匹配信息.

首先请阅读下列几种学习英浯的方法:

A. Practice speaking as often as you can-even speaking to yourself is good practice.Try recording

yourself whenever you can.

B. It helps if you can learn with someone else.If you can persuade a friend or family member to study

with you, it will make you keep working.Agree times to meet and set goals for the week.And test each

other regularly.

C. Practice improvising (即兴的) ways of getting your meaning across, even if you don't know the exact

words or phrases.Think of things you might want to say whenever you have time.An example is the use

of tenses.Use facial expressions, hand movements, anything to get your meaning across.

D. Guesswork is important in learning a new language.When listening to recorded material, you aren't

expected to understand everything the first round.If you play the same piece several times, you will most

probably understand something new each time.Learn to make maximum (最大限度) use of all the clues (提示) you can pick up.

E. A wide vocabulary is the key to successful language learning, but don't try to learn too much

vocabulary at once.

F. If you are the person on the bus, street or restaurant asking how you can improve your English, you

are on the right track.The only way to improve your speaking is by speaking.Don't worry about a bad

accent or forgetting words or not being understood.

以下是学习者在学习英语中所遇到的闲难.请将这些困难与他们所对应的学习方法匹配起来.

1. Jack's vocabulary is very small.He is very anxious to improve his English.Therefore, he wants to

enlarge his vocabulary in a short time and tries his best to memorize new words as many as possible at a

time.

2. Margret's pronunciation is poor.And she doesn't know how to improve her pronunciation.She is very

worried and doesn't know what to do.

3. Alice has difficulty in understanding the meaning of the English text.So she looks up the new words in

the dictionary in order to understand everything.However, she made little progress in English.

4. Although Peter wants to communicate with people on the bus when he is on the way home, he is

afraid of being laughed at because of his poor accent.

5. Lynne can't express herself clearly in English because she sometimes forgets some key words and

doesn't know the tenses exactly.

题型:填空题

患者右上中切牙扭转近90°角,且伴有唇侧倾斜,牙髓正常,牙根长、粗大,牙槽骨轻度吸收,牙龈红肿,探易出血。

如果选择桩冠修复,则根管治疗后开始桩冠修复的最早时间是

A.根充后2天

B.根充后3天

C.根充后1周

D.根充后2周

E.根充后任何时间

题型:填空题

A.条件(1)充分,但条件(2)不充分。

B.条件(2)充分,但条件(1)不充分。

C.条件(1)和(2)单独都不充分,但条件(1)和条件(2)联合起来充分。

D.条件(1)充分,条件(2)也充分。

E.条件(1)和(2)单独都不充分,条件(1)和条件(2)联合起来也不充分。

不等式|1-x|+|1=x|>a的解集是R.
(1)a∈(一∞,2);(2)a=2.

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