connect Leonardo to TK lcd module

I have to connect my tinkerkit LCD module to my sensor shield through serial but with my code doesn’t work. Can anyone help me?

#include <Wire.h>
#include <LiquidCrystal.h>
#include <TKLCD.h>


const int scoreSensor = 11;
const int lifeSensor = 10;

TKLCD_Serial lcd = TKLCD_Serial();

unsigned int score = 0;
unsigned int life =3;
int scoreSensorState = 0;
int lifeSensorState = 0;

void setup() {
  lcd.begin();
  lcd.clear();
  lcd.print("Hello World!");
  pinMode(scoreSensor, INPUT); 
  pinMode(lifeSensor,INPUT); 
}



void loop(){
  scoreSensorState = digitalRead (scoreSensor);
  lifeSensorState = digitalRead (lifeSensor);
 
    if (scoreSensorState==LOW) 
    {
      score = score + 10 ;
    }
    
    lcd.print(score);
    
    if (lifeSensorState==LOW) 
    {
      life = life - 1;
    }
    
    if (life = 0) score = 0;
}

the error that I find is this

sketch_pinball_machine:9: error: 'TKLCD_Serial' does not name a type
sketch_pinball_machine.ino: In function 'void setup()':
sketch_pinball_machine:17: error: 'lcd' was not declared in this scope
sketch_pinball_machine.ino: In function 'void loop()':
sketch_pinball_machine:35: error: 'lcd' was not declared in this scope

I followed the example for the serial and still I can't get it. When I try to compile the example it gives me the same erroe though.