Stone Gate pass: it is situated at ruptured stratum of Mt. Huaying, where is a natural-made pass by flood in thousands of years.

石门关——石门关是华蓥山脉地层断裂处经洪水长年冲刷而形成的天然豁口。

youdao

So a camera watching a gate through which only a dozen people pass each day would appear to be a much busier gate, with a dozen people using it in a few seconds.

ECONOMIST: Monitor

When a traveller enters an airport with one of these smart cards, sensors read the passenger's card and automatically send a gate number and electronic boarding pass to the passenger's smartphone.

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In addition, passengers must be prepared to present a local, state, or federal government-issued identification card at the boarding gate, along with the boarding pass.

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