During an earthquake, stay calm and protect yourself by dropping to the ground, taking cover under sturdy furniture, and holding on until the shaking stops. Stay indoors, away from windows, glass, and heavy objects that can fall. If you are outside, move to an open area. Do not run, panic, use elevators, or stand near buildings, power lines, or balconies. Afterward, check for injuries and follow official safety instructions.

It will be hard to go outside during the heatwave last week.

Air pollution in big cities can lead 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 into this lake, so it is polluted.