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问题 选择题

有下列几种有机物.

 （1）CH3COOCH3                            （2）CH2=CHCH2Cl

（3）CH2="CH—CHO"                其中既能发生水解反应，又能发生加聚反应的是

A．(1)与(4)

B．(2)与(3)

C．(2)与(4)

D．(1)、(3)和(4)

答案

 C

阅读理解与欣赏

阅读下面的诗歌，完成练习。     

                                                                    乡愁   

                                                           小时候   

                                                           乡愁是一枚小小的邮票   

                                                           我在这头   

                                                           母亲在那头   

                                                           长大后   

                                                           乡愁是一张窄窄的船票   

                                                           我在这头   

                                                           新娘在那头   

                                                           后来呵   

                                                           乡愁是一方矮矮的坟墓   

                                                           我在外头   

                                                           母亲在里头   

                                                           而现在   

                                                           乡愁是一湾浅浅的海峡   

                                                          我在这头  

                                                          大陆在那头

1．这首诗是按照                       顺序写的， 表达了诗人                          的思想感情。   

2．诗中，“一湾浅浅的海峡”是指                               海峡。   

3．诗人为什么把乡愁比喻成“邮票”、“船票”？

                                                                                    

4．诗人又为什么把乡愁比喻成“坟墓”、“海峡”？

                                                                                    

5．全诗你最喜欢的是                               这一句，因为                                             。
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多项选择题

属于晚期视野缺损的有（）

A.环形暗点

B.弓形暗点

C.管视

D.颞侧视岛

E.普遍性光敏感度下降
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