Greta at Montreal climate march: "we will keep on doing it until they listen" Teen climate acivist Greta Thunberg addresses people at the Montreal climate march, saying "we will keep on doing it until they listen." Thunberg urges Canadian Prime Minister Justin Trudeau and other world leaders Friday to do more for the environment as she leads half a million protesters in Montreal as part of a global wave of "climate strikes." IMAGES AND SOUNDBITES