Adverbs modify verbs adjectives and other adverbs?

Adverbs modify three things: verbs, adjectives, and other adverbs! Answer mine please? http://wiki.answers.com/Q/In_the_sentence_It_burned_last_night_is_night_an_adverb_that_modifies_when_It_burned_and_is_last_another_adverb_modifying_which_night&waAn=2