check yo breath
Used to reference an action or comment that someone has just made that is ignorant, misinformed, or otherwise just plain stupid.
Stupid guy: I believe that the war in Iraq is completely justified and agree completely with the United States' foreign policy in the Middle East.
You: Check yo breath, son! The US foreign policy shit is totally whack!
You: Check yo breath, son! The US foreign policy shit is totally whack!