It does amazingly well with schemas:

When the dead rabbit was seen by the dog, it hopped. What does "it" refer to: the rabbit or the dog?

In the sentence "When the dead rabbit was seen by the dog, it hopped," the pronoun "it" refers to the dog, not the rabbit.

This is because the rabbit is described as "dead," meaning it cannot hop or move. The verb "hopped" implies movement, which can only logically apply to the living subject in the sentence, which is the dog.

So the intended meaning is that when the dog saw the dead rabbit, the dog itself hopped, likely in surprise or reaction to seeing the dead animal.

When the iceberg was struck by the ship, it sunk. What does "it" refer to: the iceberg or the ship?

In the sentence "When the iceberg was struck by the ship, it sunk," the pronoun "it" refers to the ship, not the iceberg.

The reason is that icebergs, being large masses of ice floating in water, do not actually "sink" when struck. They are already floating and may crack or break apart when struck, but the word "sunk" implies something going down below the water's surface.

Ships, on the other hand, are vessels designed to float on water. If a ship strikes an iceberg with enough force, it can cause damage that leads to the ship taking on water and eventually sinking below the surface.

So in this context, with the verb "sunk" being used, it is more logical that "it" is referring to the ship sinking after striking the iceberg, rather than describing what happened to the stationary iceberg itself.