1.During an earthquake, you should stay calm, drop to the ground, take cover under a sturdy piece of furniture (like a table), and hold on until the shaking stops. Stay away from windows and heavy objects that might fall. You shouldn't run outside, as it can be more dangerous.

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

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

1.Unless this store sells emergency kits, I'll check the other one. 2.If you throw trash into the river, it will become more polluted.

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