book

 

 

Learn English  
 

Blue Level

 
 

Red Level

 
 

Yellow Level

 
 

Green Level

 
 

Purple Level

 
 

Orange Level

 
 

Violet Level

 
 

Video Lessons

 
 

Links

 
 

American Speech

 
 

Chat

 
 

How to Learn

 
 

Vocabulary

 
 

U.S. Citizenship

 
 

Reading

 

 

 

 


 

filter  

 

A filter is a type of screen that allows liquids or air to pass through while trapping sold, unwanted substances:

  • An air filter removes dirt in the air as it goes through a machine.
  • A gas filter in your car traps impurities found in gasoline.
  • A coffee filter is used in a coffee maker. The filter allows water to pass through the coffee grounds.
  • I have to change the furnace filter in my house every few months because it gets dirty.
  • A vaccum cleaner has a filter that traps very small particles of dirt and dust.
  • Saltwater must go through a filtration process in order to separate the salt from the water. (The word "filtration" is also a noun.)

coffee filters These are coffee filters.

It's possible to use "filter" as a verb. In this case, it's in reference to the screening or selection of people or things.

  • Applicants for jobs are filtered through the interview process.
  • The media act as a filter for stories that are fake.
  • Football tryouts filter out the players who aren't good enough to make the team.
  • Immigrants who enter the United States are filtered though Homeland Security which checks people for criminal backgrounds.

Click here to learn more vocabulary.

Date of publication: December 8, 2016

 

 

 

 

 

 

© 2018 Learn American English Online. All rights reserved.