Grammar hub: First conditional Match the sentence halves. If you put plastic in the organic waste bin, 1 1 2 If Aiden starts going to school in a shared car, 3 Unless we reduce pollution soon, 4 If Aiden doesn't turn off the tap, a he will VIDEO 09 waste a lot of water. b there will be serious problems around the world. c they won't recycle it. d it will help to reduce pollution. 4​