In the following sentence, "People eat garlic when it is raw or cooked." is "when it is raw or cooked." an adverbial clause or an adjective clause? The way I see it, this clause can either talk about garlic or eating. Adverbs answer "how" questions and "when" can answer "how."
Other examples that fit this model:
"Vampires leave their coffin when it's dark." "When it's hot, I drink cold beers." "You use a pen when you are certain." "I get a cough when it's cold."
Is "when" a word that can introduce two interpretations of a sentence, a sort of "wavicle" (to borrow from the world of quantum mechanics)?