void setup(){
  Serial.begin(115200);
  if(!Serial) Serial.println("serial is not ok");
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(10, OUTPUT);
  delay(300);
}
void loop(){
  
  digitalWrite(10, HIGH);
  Serial.println("green is on");
  delay(2000);
  digitalWrite(10, LOW);
  Serial.println("green is off");
  digitalWrite(9, HIGH);
  Serial.println("yellow is on");
  delay(600);
  digitalWrite(9, LOW);
  Serial.println("yellow is off");
  digitalWrite(8, HIGH);
  Serial.println("red is on");
  delay(1800);
  digitalWrite(9, HIGH);
  Serial.println("yellow is on");
  delay(400);
  digitalWrite(8, LOW);
  Serial.println("red is off");
  digitalWrite(9, LOW);
  Serial.println("yellow is off");
}