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【化学一选修5：有机化学基础】

化合物M是二苯乙炔类液晶材料的一种，最简单的二苯乙炔类化合物是，以互为同系物的单取代芳烃A、G为原料合成M的一种路线（部分反应条件略去）如下：

回答下列问题：

有机化合物甲、乙用于制备化妆品，二者合成路线如下（部分产物及条件略）。

已知：

（-R、-R’代表烃基或-H）

A、B、C、D、E、F、G、H八种主族元素分布在三个不同的短周期，它们在周期表中位置如下：

请回答下列问题：

[物质结构与性质]

丁二酮肟是检验Ni2+的灵敏试剂。

碳碳双键在酸性高锰酸钾溶液中发生断键氧化过程：

完成下列填空：

Dogs are often【C1】______man’s best friend. For those who are blind, a dog is【C2】______than a friendly company. A dog is a pair of sharp eyes. A【C3】______dog guide gives blind people the【C4】______to move through the world safely and freely. A dog guide is also a best friend. 【C5】______a working team of a dog and a person is not easy. There are no factories making thousands of dog guides a day. There are however, schools all【C6】______the country that train both blind people and the dogs they depend upon. The process of education is long for both the dog and its human partner. A dog begins schooling as puppy. Around age of 8 weeks, the puppy is placed with a faster family. There it【C7】______training and gets used to【C8】______around people. When a dog is about a year old, it goes off to school for a series of tests. These tests help the school【C9】______whether the dog is likely to make a good guide. Dogs that fail the tests are placed in permanent homes. 【C10】______that pass the tests go into a training【C11】______ For the next four-to-six months, the dog learns everything【C12】______needs to become a dog 【C13】______The dog learns to stay focused. It learns to ignore food, smell and other animals. It learns to remain【C14】______by such noises such【C15】______shouting or music from a passing car radio. It learns to【C16】______commands like "right", " left" or " forward ". The dog learns to stop before every curb and stairway and to【C17】______moving objects. In short, good dog guides learn to keep their【C18】______safe while they go about the everyday actions of life. A dog that【C19】______completed training will be【C20】______a master.【C8】

A．being
B．be
C．goes
D．walk