Public Address systems (PA systems) are commonly used in American malls, airports and grocery stores.

公共广播系统在美国的商场、机场、和杂货店普遍使用。

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Public Address systems (PA systems) are commonly used in American malls, airports and grocery stores.

公共广播系统在美国的商场、机场、和杂货店普遍使用。

youdao