Pollution control measures are either not strict or nonexistent, leading to choking clouds of smog.

污染控制措施不严格或不存在，导致令人窒息的雾霾。

Even countries who practice strict pollution control measures may still be affected by countries adjacent to or adjoining them, when air pollution permeates the air.

当空气污染弥漫在空气中时，即使采取严格污染控制措施的国家仍可能受到邻近或毗邻国家的影响。