Answer the questions based on the Shijiazhuang weather forecast and air quality daily information provided in the table below. Shijiazhuang City October 24th October 25th Weather Forecast

① Combined with the diagram, we know: means fog turns to cloudy; means cloudiness turns to sunny; northwest wind level 6;

②Air pollution index refers to the degree of air pollution, the greater the index , the more serious the air pollution, the level of air quality is affected by natural factors on the one hand, and human activities on the other hand.

So the answer is: ① Fog turns to cloudy; cloudy turns to clear; Northwest; Level 6; ② Good; natural factors; human activities.