开启和关闭的原因可能是光线的不同。

The cause of the opening and closing is probably the difference in light.

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现在我们有了一台可以开启和关闭的自动售货机。

Now we have a vending machine that we can turn on and off.

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上述设置对于多次开启和关闭连接的测试程序工作得很好。

The Settings shown above worked fine with a test program that opened and closed a connection several times.

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