Answer: Roger’s throwing a large rock down the mountain and killing Piggy.
Foreshadow occurs when an author gives you a hint of what is going to happen later in the story. In this case, the author tells us that Roger threw a rock at a littleun. This event is the first time we have an indication of the fact that the children are likely to resort to violence. In fact, violence will dominate the story soon, and it will find its most obvious example in Roger throwing a large rock down the mountain and killing Piggy.
