Making an animation play when you press down 2 keys

Hello Unity Community!
Im making a game and I need to make some animations (Like sprint, Walking and Idle) I’ve made them all and I’ve assigned a key for each animations. But say for the sprinting animation when you press “rightshift” it plays the animation but he doesn’t move. So I wanted to make it so when you press “w” and “shift” together it plays the “Sprint” animation. This is the java script I’m using to play the animations.

//Key down 
     function Update()
{
 if(Input.GetKeyDown("w"))
 {
  // Plays the walk animation - stops all other animations
  animation.Play("walk", PlayMode.StopAll);
 }
}

could I add something to this code that would work? If so what? And is it possible to give me an example?
Thank you
-Stuart

The easy thing to do would be:

if(Input.GetKeyDown(KeyCode.W) && Input.GetKey(KeyCode.LeftShift))

Note this means the shift key must already be down when the ‘W’ key is pressed (which is the usual way I see these keys pressed). A more general solution is more work.