Cannabis smoking
Cannabis smoking ( or colloquially smoking pot ) is the inhalation of smoke or vapors released by heating the flowers , leaves , or extracts of cannabis and releasing the main psychoactive chemical , Δ9-tetrahydrocannabinol ( THC ) , which is absorbed into the bloodstream via the lungs . 
<triplet> cannabis <subj> tetrahydrocannabinol <obj> has part