二尖瓣后叶关闭不全（）。 A.颈部和锁骨上窝 B.左腋下和肩胛下区 C.胸骨左缘和心

阅读下面的文言文，完成下面问题。

　　乐恢字伯奇，京兆长陵人也。父亲，为县吏，得罪于令，收将杀之。恢年十一，常俯伏寺门，昼夜号泣。令闻而矜之，即解出亲。恢长好经学，事博士焦永。永为河东太守，恢随之官，闭庐精诵，不交人物。后永以事被考，诸弟子皆以通关被系，恢独皦然不污于法，遂笃志为名儒。后仕本郡吏，太守坐法诛，故人莫敢往，恢独奔丧行服（行服：守孝、服丧）。归，复为功曹，选举不阿，请托无所容。同郡杨政数众毁恢，后举政子为孝廉，由是乡里归之。辟司空牟融府，会蜀郡太守第五伦代融为司空，恢以与伦同郡，不肯留，荐颍川杜安而退。诸公多其行，连辟之，遂皆不应。

　　后征拜议郎。会车骑 * * 窦宪出征匈奴，恢数上书谏争，朝廷称其忠。入为尚书仆射。是时河南尹王调、洛阳令李阜与窦宪厚善，纵舍自由。恢劾奏调、阜，并及司隶校尉。诸所刺举，无所回避，贵戚恶之。宪弟夏阳侯瑰欲往候恢，恢谢不与通。宪兄弟放纵，而忿其不附己。妻每谏恢曰：“昔人有容身避害，何必以言取怨？”恢叹曰：“吾何忍素餐立人之朝乎？”遂上疏谏曰：“臣闻百王之失，皆由权移于下。诸舅不宜干正王室，以示天下之私。政失不救，其极不测。方今之宜，上以义自割，下以谦自引。”书奏不省。时窦太后临朝，和帝未亲万机，恢以意不得行，乃称疾乞骸骨。窦宪因是风厉州郡迫胁。恢遂饮药死。弟子縗絰挽者数百人，庶众痛伤之。后窦氏诛，帝始亲事，恢门生何融等上书陈恢忠节，除子己为郎中。（《后汉书·乐恢传》）

1．对下列句子中划线词的解释，不正确的一项是[ ]

A．令闻而矜之，即解出亲——矜：怜悯、同情

B．选举不阿，请托无所容——容：宽容、容忍

C．诸公多其行，连辟之——多：称赞、赞扬

D．以示天下之私——私：私有的、私人的

2．下列对原文有关内容的概括和分析，不正确的一项是[ ]

A．乐恢为人至孝。父亲因得罪了县令而被关押，年幼的乐恢昼夜痛哭不已，他的行为感动了县令，最后父亲得以释放。

B．老师焦永“以事被考”后，乐恢“不污于法”，拒绝为他托关系，找门路；后来焦永终因犯法被杀，他“独奔丧行服”：这与他的性格有关。

C．蜀郡太守第五伦与乐恢是同郡之人，所以当第五伦取代牟融为司空时，乐恢在推荐了杜安之后，坚决请退，表现了他为人正直的一面。

D．河南尹、洛阳令与权贵窦宪相互勾结，为非作歹。乐恢不畏权贵，上书弹劾窦宪兄弟，因窦太后的庇护，劝谏不但没有成效，自己反而被迫害而死。

3．把文中加横线的句子翻译成现代汉语。

（1）同郡杨政数众毁恢，后举政子为孝廉，由是乡里归之。

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（2）昔人有容身避害，何必以言取怨？

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下面关于硝化细菌和蓝藻共同点的叙述，正确的是

①都是原核生物 ②都是自养生物 ③都是单细胞生物 ④都是需氧型生物[ ]

A．只有①

B．只有①②

C．只有①②③

D．①②③④

蕨类植物一般采用（）或（）方法繁殖。

阅读理解。

                                                          Community College

      Here I am, a senior. After four years of high school, I have learned a lot of lessons.

Some were good and valuable. And I have also learned others just from growing up and

being around other teenagers.

      I started senior year with a 1.5 GPA (＝grade point average平均分,相当于65%),

which is not even close to what I am capable of. The last three years I fooled_around and

cut lots of classes. Now, I can easily say that it is the only thing in life that I regret. Next year

I will watch most of my friends go to college while I lost that chance. This does not mean that

I am giving up on my dreams, but when I started high school, my goal was to get great grades

and go to a competitive college.

      At first I blamed the people around me for my bad experiences, but I've learned that it's my

fault when bad things happen. In the last three years I realized that I am the only one in control

of myself. While making my teachers and my peers the excuse for not wanting to go to class, I

developed a huge lying problem.

      If I could start over, I would in a heartbeat, but I can't, so instead of beating myself up, I try

talking to younger teenagers about the importance of doing well in school by explaining the situation

I got myself into. Community college looks like a great opportunity. I am looking forward to taking

many credits and receiving good grades. I see community college as a year to turn my life around.

It's my ticket out of here to wherever I want to go. I have another chance to make my future and

I've promised myself I won't mess up.

      We need to study history so we won't repeat our past; I've studied my personal history, and

will avoid my mistakes in the future. I am ready for the next task in life, the only question is, is it

ready for me?

1. The author takes the community college seriously because he wants to ________.  

A. show his ability to be one of the top students

B. prove that others did wrong to him before

C. improve himself and win others' respect

D. get the opportunity to apply for a good job

2. Which of the following is NOT the author's advice?

A. To behave well at school is necessary.

B. Others should be blamed for our hard time.

C. Learn from past, don't make mistakes.

D. Be hopeful, choose community college.

3. From the passage, we know that the author is ________.

A. easygoing and hard working                        

B. confident and responsible

C. sensible and independent              

D. honest and ambitious

4. The underlined phrase "fooled around" in the second paragraph means "________"．  

A. wasted time    

B. played tricks

C. made faces          

D. felt ashamed

试述机车轮箍弛缓的原因及检查判断方法。