I dropped a quarter into the slot of the pay phone.

我往付费电话的投币口里投了一枚25分的硬币。

《柯林斯英汉双解大词典》

Told me you come in there last week, got a handful of change, and fed it into the pay phone outside.

她告诉我，上周你去过那里，换了一些零钱，投入外面的公用电话。

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But the new contest hopes to create a new purpose for the pay phone.

CNN: Is the pay phone making a comeback?

But to stay relevant, the pay phone of the future needs to offer valuable services at all times, not just during emergencies.

CNN: Is the pay phone making a comeback?

The pay phone is indeed a boon to the poorer class.

CNN: Pay phones: The search for an endangered species