Fill in the Blanks zero conditionalOnline version A guide to check the understanding of the zero conditional. by Raúl González Saavedra 1 step breathes not arrive does stops do stops am not swim do not sing is fall 1 . If the chickens cross the road , they finally ( to arrive ) home safely . 2 . If we ( to sing ) very loudly , neighbours are not happy . 3 . If I ( to be ) very tired , I always yawn . 4 . If I go forward , I ( not / to step ) back . 5 . If he ( to stop ) breathing , he starts choking . 6 . If he wears braces , his trousers ( not / to fall ) . 7 . If a car is out of fuel , it ( to stop ) beside the road . 8 . If a plane ( to be ) out of fuel , it falls . 9 . If he ( not / to swim ) anymore , he sinks in deep waters . 10 . If she ( to breathe ) , she lives .