下列命题是假命题的是（ ） A．对于两个非零向量a、b，若存在一个实数k满足a=k

读写任务(共1小题；满分25分)

阅读下面的短文，然后按照要求写一篇150词左右的英语短文。

In the atmosphere, carbon dioxide acts rather like a one-way mirror —— the glass in the roof of a greenhouse which allows the sun’s rays to enter but prevents the heat from escaping.

According to a weather expert’s prediction, the atmosphere will be 3℃ warmer in the year 2050 than it is today, if man continues to burn fuels at the present rate. If this warming up took place, the ice caps in the poles would begin to melt, thus raising sea level several metres and severely flooding coastal cities. Also, the increase in atmospheric temperature would lead to great changes in the climate of the northern hemisphere, possibly resulting in an alteration of earth's chief food-growing zones.

In the past, concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet. But the weather experts are now paying more attention to West Antarctic, which may be affected by only a few degrees of warming, in other words, by a warming on the scale that will possibly take place in the next fifty years from the burning of fuels.

Satellite pictures show that large areas of Antarctic ice are already disappearing. The evidence available suggests that a warming has taken place. This fits the theory that carbon dioxide warms the earth.

However, most of the fuel is burnt in the northern hemisphere, where temperatures seem to be falling. Scientists conclude, therefore, that up to now natural influences on the weather have exceeded those caused by man. The question is: Which natural cause has most effect on the weather?

【写作内容】

1.以约30个词概括短文的要点；

2. 然后以约120个词就“Solutions of slowing climate change”为主题写一篇短文，包括如下要点：

(1) 你认为地球会不会持续变暖；

(2) 其原因是什么以及人类在其中的作用；

(3) 谈谈你的建议。

【写作要求】

(1) 你可以使用实例或者其他论述方法支持你的观点，也可以参照阅读材料的内容，但不得直接引用阅读材料中的句子。

(2) 字迹清楚，书写工整。

【评分标准】 概括准确，语言规范，内容合适，篇章连贯。

肝性脑病时神经递质的变化有（）

A.去甲肾上腺素、多巴胺下降

B.假性神经递质增加

C.γ-氨基丁酸增加

D.谷氨酰胺减少

E.5-羟色胺增加

"It’s no use, Mum," said Johnny. "I’m just no good at dancing."

"You’ve got to keep trying. Tonight will be (1) , dear. Try a turn with that pretty Lisette. "

Johnny (2) . Every Saturday night used to be the best of the week. He and his parents went to the (3) at the Club, where his hero, Alcide, played the accordion with the band. But lately everything had changed. Now that Johnny was older, he was (4) to dance with a girl!

(5) Johnny and his parents arrived at the Club, music had already started. Johnny got up his (6) to approach Lisette. "May I have this dance" Johnny asked. "That’s all right."said Lisette. Johnny struggled to keep up with Lisette’s (7) steps, but he was always one beat behind her. Then Johnny heard his friend Pierre say, "Look! Johnny has two left feet!" (8) burst from the crowd. Johnny (9) and ran outside, determined never to go to another dance.

The next Saturday, Alcide (10) to Johnny’s house for some potatoes. He happened to hear Johnny playing the accordion. Alcide’s eyes (11) . "Bring that accordion and play some songs tonight," Alcide said. Then he drove off, leaving Johnny staring open mouthed (12) him.

At the Club, Johnny scanned the crowd for Lisette and (13) her. The band played for a long time before Alcide said, "Dear friends, I got a (14) for you tonight. Young Johnny is going to join us!" (15) , Johnny stepped up on the platform, his eyes on the floor. He began to play, and the band (16) behind him. When the song ended, he heard cheers. Johnny kept playing until the dance was (17) . "You did a fine job tonight. Play with us again next Saturday night, " Alcide said. "Yes, sir! " said Johnny. (18) he went outside, Johnny saw Lisette and her friends near the door. Lisette stepped (19) , smiling. "You played really good tonight!" she said."Thank you," Johnny blushed. As he walked on, Pierre (20) moved out of the way for him to pass.Johnny patted his accordion. Come to think of it, in his whole life, he had never once seen Alcide out on the dance floor.

9().

A．broke away

B．went out

C．broke up

D．turned out

应急通信系统必须有效地满足指挥调度等应急通信保障需求。

水工建筑物按用途可分为（）；（）；（）；（）；（）；（）。