snow isn't so clean

colleague

• teacher

• coworker

• college student

• student

exist

• free from germs

• to continue to be present

• to no longer be present

• to make ill

sterile

• free from dirt

• free from germs

• free from water

• free from infection

bacteria

• tiny drops of water

• dirt in the air

• tiny living things that can make people healthy

• tiny living things that can make people sick

banish

• to continue to be present

• to get rid of something completely

• dirt in the air

• to make ill

pollution

• free from germs

• to make ill

• dirt in the air or water

• water in the air

infect

• to make healthy

• to make ill

• to be present

• to cause something to happen

vapor

• tiny living things that can make people sick

• tiny dirt in the air

• tiny drops of liquid in the air

• tiny living things that can make people healthy