问题
单项选择题
在由继电器组成的顺序控制装置中，组合开关主要作为（）引入开关使用。
A、电源；
B、输入信号；
C、设备状态信号；
D、控制指令。
答案
参考答案：A
搜题请搜索小程序“爱下问搜题”
在由继电器组成的顺序控制装置中，组合开关主要作为（）引入开关使用。
A、电源；
B、输入信号；
C、设备状态信号；
D、控制指令。
参考答案：A
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| As she walked round the large shop, Edith realized how difficult it was to choose a suitable Christmas 1 for her father. She 2 that he were as easy to please as her mother, who was 3 satisfied with perfume (香水). 4 , shopping at this time of the year was a most 5 job. People 6 on your feet, pushed you with their shoulders and almost 7 you over in their hurry in order to 8 something cheap ahead of you. Partly to have a rest, Edith paused in front of a counter, where some beautiful ties were on 9 . "They are 10 silk," the shop assistant told her with a smile trying to 11 her to buy one. But Edith knew from past 12 that her choice of ties hardly ever pleased her father. She moved on slowly and then, quite by chance, 13 where a small crowd of men had gathered round a counter. She found some fine pipes (烟斗) on sale and the 14 were very beautiful. Edith did not hesitate for long, although her father 15 smoked a pipe once in a while, she believed this was 16 to please him. When she got home, with her small but 17 present hidden in her handbag, it was time for supper and her parents were already 18 table. Her mother was in great 19 . "Your father has at last decided to stop smoking," she told her daughter happily. Edith was so 20 that she could not say a single word. | ||||
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