1.It was hard to go outside during the heatwave last week

2 Air pollution is big cities can lead to serious health problems.

1 . Unless this store doesn’t sell emergency kits, I’ll check the other one.

2 . If you  throw trash into the river, or it will become more polluted.

3 .The factory  is dumping waste in it because this lake is polluted 

1: It was hard to go outside during the heatwave last week.

2 If you throw trash into the river, or it will become more polluted

3.The factory is dumping waste in it because this lake is polluted