1.The smoke from the car__the air.That's why the air is__..(

1.The smoke from the car__the air.That's why the air is__..(pollute)
2.We must pay attention to the__,if it turns red,we can't cross the road,When it is rush hour,we'd batter not go shopping because there is too much__.(traffic/traffic lights)
3.Please hold your__,the less dirty air you__into,the healthier you will be.(breath)