This could simply mean two things: you could have made a mistake while copying the commands, or you should still set the correct language for the TurtleScript commands (you can do that by choosing the Settings → Script Language submenu). This makes reading large blocks of code more easy.
That the color of the code changed while you where typing it: this feature is called intuitive highlighting - different types of commands are highlighted differently. This because you have used the forward and the turnleft commands. That - after executing the commands - the turtle moves up, draws a line, and then turns a quarter turn to the left.
