Turtles can determine whether a number is above or below another number. Let's write a program that asks how old you are: ```python.run import turtle tina = turtle.Turtle() tina.shape('turtle') tina.penup() try: age = int(input("How old are you? (Use numbers)")) if age >= 10 and age <= 15: tina.write("You're between 10 and 15 years old") tina.backward(20) elif age < 10: tina.write("You're less than 10 years old") tina.backward(20) elif age > 15: tina.write("You're over 15 years old") tina.backward(20) except: tina.backward(100) tina.write("I don't think I understand that age. Are you using numbers?") tina.backward(20) ``` **Advanced:** In the example above you'll see there are `try:` and `except:`. These lines try to run code that comes after `try:`, and if any errors happen, do what's in the `except:` section. This is how Tina knows whether you put in a real number like `15`. This is how real programmers change the behavior of programs based on any errors that might come up.