There is a whirlpool or dead zone below the main water flow zone when the flow changes and the size of which is related to flow but its location basically unchanged.

当流量在一定范围内变化时，主流区下方均有漩涡低速区或死水区，该区域的大小与流量有关，其位置基本不变。

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You can add the location as well, although it requires the phone to have a working GPS or network connection, so you can't get the information while on a subway or in a dead zone.

你也可以加入地点资讯，但这要求手机开通了GPS或网路连接，因此你在地铁里或无信号区时无法获得这种资讯。

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