Sentence:A Philippine Airforce aerial shot shows residents standing on a rooftop to escape the [e1]floodwaters[/e1] caused by continuous [e2]rains[/e2] brought on by Typhoon Ketsana in Marikina city, metro Manila September 27, 2009.
 e1: floodwaters. 
 e2 : rains.
Answer: Cause-Effect(e2,e1)