P or — protocol: This generic protocol match is used to check for certain protocols.

p或——protocol：该通用协议匹配用于检查某些特定协议。

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P When this object goes from o to P, that takes a certain amount of time.

当物体从O到，需要一定的时间。

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S When it goes from P to s, back to the ground, that takes also a certain amount of time.

当它从P到，到地上，需要一定时间。

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People who are trying to maintain separate work and personal lives may even set this to work after they leave the office, only allowing calls from certain groups (like family and close friends) to ring between 6 p.m. and 8 a.m.

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