var myFish1 = ['angel', 'clown', 'drum', 'sturgeon'];
var removed1 = myFish1.splice(2, 1, 'trumpet');

// myFish1 is ["angel", "clown", "trumpet", "sturgeon"]
// removed1 is ["drum"]

var myFish2 = ['angel', 'clown', 'drum', 'sturgeon'];
var removed2 = myFish2.splice(-2, 2, 'trumpet');

// myFish2 is ["angel", "clown", "trumpet"]
// removed2 is ["drum", "sturgeon"]