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I'm doing the Pimsleur method. I can't figure out the difference between the three forms: l'essence vs. d'essence vs. de l'essence
When does one use which, and how can one apply these rules more broadly to other words?
(I know that de l'essence is supposed to be "some gas" and l'essence is supposed to be just "gas" ... but in the examples in Pimsleur, there seem to be some exceptions where it's not so strict. I think it has to do with how the French say "de" even when they don't explicitly mean "some".)