Hold down 2 buttons and do something

I wonder how to make if I hold down W and Shift it will do something.
I think I should do It like this but I’m not sure

if(Input.GetKey("W" && "LeftShift");
function blahblah()

I think, change your code to

 if(Input.GetKey("W") && Input.GetKey("LeftShift")) {
  //this is your function blahblah