Have you ever paid attention (注意)to the Air Quality Index (空气质量指标) or AQI reported in the newspaper? The AQI helps us understand what the air quality around us means to our health. The AQI uses colours, numbers and words to tell us about the air. Let’s see what these colours and numbers mean.

AQI colours	AQI numbers	Health words	What to do
Green	0~50	Good	Just enjoy the clean air
Yellow	51~100	Moderate (适中的)	Air Quality is fine for most people
Orange	101~150	Unhealthy for sensitive(敏感的) groups	Active children and adults and people with lung (肺) disease (疾病) should spend less time outdoors.
Red	151~200	Unhealthy	People with lung disease and active kids and adults shouldn’t spend too long time outdoors. Everybody else should try to spend less time outside.
Purple	201~300	Very unhealthy	People with lung disease and active kids and adults should not spend any time outdoors. Everybody else should try not to go outside.

If the weather report says today’s AQI is 39, we can __________.

A．enjoy the clean air

B．spend less time outside

C．try not to go outside

D．stay inside most time

If the Air Quality Index is _______, the air quality is good for most people.

A．orange

B．red

C．purple

D．yellow

The _______ AQI numbers are, the _________ air quality is.

A．bigger; better	B．bigger; nicer
C．smaller; better	D．smaller; worse (糟糕)

We use ________ to tell about the quality of the air.
① colours ② words ③ weather ④ numbers

A．①②③④	B．①②③
C．①②④	D．②③④

Which of the following is TRUE?

A．If the AQI number is 140, the AQI colour will be red.

B．If the AQI colour is purple, the air is the best for people.

C．People with lung disease are very sensitive to the air.

D．The AQI can’t help people know the air quality.