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问题 选择题

关节腔内的滑液，其作用是减少运动时的摩擦，与减少摩擦的结构还有（　　）

A．关节囊

B．关节软骨

C．关节头

D．关节窝

答案

关节是由关节面、关节囊和关节腔三部分组成．关节面包括关节头和关节窝．使关节牢固的结构特点是：关节囊及囊里面、外面的韧带．使关节运动灵活的结构特点是：关节面上覆盖一层表面光滑的关节软骨和关节囊的内表面还能分泌滑液，可减少运动时两骨间关节面的摩擦和缓冲运动时的震动．关节腔由关节囊和关节面共同围成的密闭腔隙，内有少量滑液．滑液有润滑关节软骨的作用，可以减少骨与骨之间的摩擦，使关节的运动灵活自如．选B

故选：B

单项选择题

Roger Federer Lights up the Arabian Night
罗杰·费德勒点亮阿拉伯之夜


Plenty of people will be glad Tim Henman was not here to trouble Roger Federer once more last night，as the seedings said he should have been.Popular with the expatriates though he may be，and capable of upsetting Federer though he undoubtedly is，there is nothing quite so stirring as seeing one of the most gifted world No l s of all in full cry.
Instead of struggling with his jinx player，Federer imposed a spell of his own.He beat Andrei Pavel，whom Henman beat in the Paris Masters final，by6-3，6-3，and strode the court like a ruler who knows his aura is expanding.
It carried the Swiss imperiously into a semi-finals of the Dubai Championships，where he will face Jarkko Nieminen.The Finn earned his place by defeating the Dutch No 8 seed Sjeng Schalken 6-3,6-3.
Federer insisted he was not at his best-"I haven’t wanted to chase the fines as much as I should，"he said.
Pavel was driven to distraction as it was.He had akeady lifted himself near the level he showed when he was in the top 20.But just when he looked as if he might prolong the second set， Federer struck.
He retrieved one ball from deep，outside the tramlines on the forehand side，turned and reached the next ball from short and outside the tramlines on the backhand side，and still somehow hit a controlled winner.It completed the decisive break of serve.
Pavel responded by launching a spare ball towards the sky and it landed on the whiskey tables in the lrish village below.The umpire uttered a code violation warning in little more than a whisper.It was as though he felt sympathy for the Romanian.
If Federer reaches tomorrow’s final he will play Spain’s Feliciano Lopez，whose Davis Cup debut came in the singles in the 2003 final in Melbourne，or Mikhail Youzhny，whose first Davis Cup experience was as a ball boy in the 1995 final in Moscow.
That spurred Youzhny to make a top-level breakthrough seven yearslater，and to develop perseverance which has been revealed this week in a 6-3，1-6，6-1 quarter-final win over Rafael Nadal yesterday in heat which would have made a camel protest，and in a recovery from two days’vomiting after eating Japanese seafood."My cap felt as if it weighed five kilos."he said.

It seemed that Andrei Pavel______.

A．played nearly at his highest level during the match
B．nearly beat Federer in the second set
C．had a break of serve by Federer
D．was completely controlled by Federer
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单项选择题

He felt insulted at the comment that his writing was all______.

A．junk

B．pollutant

C．garbage

D．waste
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