Robot Code Problem

Hello i have make a robot(its not mine i see on internet) that use 2 motors. I want to run 4 motors.I modify the code but it's say Error compiling.Can you help me plase?The code is

#include <AFMotor.h> //import your motor shield library
#define trigPin 12 // define the pins of your sensor
#define echoPin 13
AF_DCMotor motor1(1,MOTOR12_64KHZ); // set up motors.
AF_DCMotor motor2(2,MOTOR12_8KHZ);
AF_DCMotor motor3(3,MOTOR34_64KHZ);
AF_DCMotor motor4(4,MOTOR34_8KHZ);

void setup() {
Serial.begin(9600); // begin serial communitication
Serial.println("Motor test!");
pinMode(trigPin, OUTPUT);// set the trig pin to output (Send sound waves)
pinMode(echoPin, INPUT);// set the echo pin to input (recieve sound waves)
motor1.setSpeed(105); //set the speed of the motors, between 0-255
motor2.setSpeed (105);
motor3.setSpeed (105);
motor4.setSpeed (105);
}

void loop() {

long duration, distance; // start the scan
digitalWrite(trigPin, LOW);
delayMicroseconds(2); // delays are required for a succesful sensor operation.
digitalWrite(trigPin, HIGH);

delayMicroseconds(10); //this delay is required as well!
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
distance = (duration/2) / 29.1;// convert the distance to centimeters.
if (distance < 25)/*if there's an obstacle 25 centimers, ahead, do the following: */ {
Serial.println ("Close Obstacle detected!" );
Serial.println ("Obstacle Details:");
Serial.print ("Distance From Robot is " );
Serial.print ( distance);
Serial.print ( " CM!");// print out the distance in centimeters.

Serial.println (" The obstacle is declared a threat due to close distance. ");
Serial.println (" Turning !");
motor1.run(FORWARD); // Turn as long as there's an obstacle ahead.
motor2.run (BACKWARD);
motor3.run (FORWARD)
motor4.run (BACKWARD)
}
else {
Serial.println ("No obstacle detected. going forward");
delay (15);
motor1.run(FORWARD); //if there's no obstacle ahead, Go Forward!
motor2.run(FORWARD);
motor3.run(FORWARD)
motor4.run(FORWARD)
}

}

The message of the error is this

Arduino: 1.6.3 (Windows 7), Board: "Arduino Uno" Obstacle_Avoiding_Robot_Code.ino: In function 'void loop()': Obstacle_Avoiding_Robot_Code.ino:53:5: error: expected ';' before 'motor4' Obstacle_Avoiding_Robot_Code.ino:61:5: error: expected ';' before 'motor4' Error compiling. This report would have more information with "Show verbose output during compilation" enabled in File > Preferences.

These lines need a ; at the end
motor3.run (FORWARD)
motor4.run (BACKWARD)

motor3.run(FORWARD)
motor4.run(FORWARD)

    motor3.run (FORWARD)
    motor4.run (BACKWARD)

No terminating semicolons.

Thank you very much for your help.