NSString *startString = @"3, 2, 1, go!";
startString = [
               startString stringByReplacingOccurrencesOfString:@"1" withString:@"one"];
startString = [
               startString stringByReplacingOccurrencesOfString:@"2" withString:@"two"];
startString = [
               startString stringByReplacingOccurrencesOfString:@"3" withString:@"three"];
//startString = "three, two, one, go!"