In grammar, a angling modifier attaches itself to a word different from the one the writer apparently meant. When such modifiers are participles, they often appear at the beginning of sentences. For instance, in the sentence, "Walking down Main Street, the trees were beautiful," the "walking down" modifier seems to connect to "the trees" in the sentence, when on reflection it really connects to the invisible speaker of the sentence. He or she is the one walking down the street (and finding the trees beautiful). Thus, the modifier is hanging on nothing, therefore dangling.