Since the lungs have to work harder to get oxygen into the blood in high altitudes, alcohol is absorbed into the blood system quicker, speeding up the effect that a couple of drinks would normally have.
(the effect; would normally have; a couple of drinks) (the lungs; to work harder; to get oxygen into the blood in high altitudes) (alcohol; is absorbed quicker; speeding up the effect)
the effect the lungs alcohol
would normally have to work harder is absorbed quicker
a couple of drinks
to get oxygen into the blood in high altitudes
speeding up the effect