Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes What I need to know about Gas ?
    ### Response:
    Gas in the digestive tract is usually caused by swallowing air and the breakdown of certain foods in the large intestine.
                
*See the Pronunciation Guide for tips on how to say the underlined words.
                
You typically swallow a small amount of air when you eat and drink.
    