difference

Without my looking these words up, I will offer what they suggest to me:

(1) conserve is to use sparingly or save something by doing so

(2) preserve is to save by maintaining a status quo

(3) reserve is to set aside for later use

I don't know how much this helps, but it's a start

Thank you bermbits. It did help me. Particualry the word "sparingly" helped me.

Me again - be aware of the fact that each word has several other meanings as well, but I think this is what you wanted.

Glad to have helped.