#define red 8
#define yellow 9
#define green 10


void setup() {
 pinMode(red, OUTPUT);
pinMode(yellow, OUTPUT);
pinMode(green, OUTPUT);
Serial.begin(9600);
}

void loop() {
 digitalWrite(red,HIGH);
digitalWrite(yellow,LOW);
digitalWrite(green, LOW);
 Serial.println("red is on yellow is off green is off");
 delay(2000);
  digitalWrite(red,LOW);
digitalWrite(yellow,LOW);
digitalWrite(green, HIGH);
 Serial.println("red is off yellow is off green is on");
 delay(2000);
  digitalWrite(red,LOW);
digitalWrite(yellow,HIGH);
digitalWrite(green, LOW);
 Serial.println("red is off yellow is on green is off");
 delay(1000);
 
 
 }