Now the dog pulls harder, so its arrow is 6 squares long against Bodhi's 4.

Are the forces on the toy equal or unequal?

The dog's arrow is 6 squares long and Bodhi's is 4. The forces on the toy are unequal.

They are unequal, because the dog's pull is stronger.

Two opposite forces of different strengths are called unequal forces.

Now Bodhi pulls harder too, until his arrow is 6 squares long.

Are the forces on the toy equal or unequal?

Both arrows are 6 squares long again. The forces on the toy are equal.

They are equal again.

And now Bodhi pulls hardest of all, so his arrow is 7 squares long against the dog's 6.

Are the forces on the toy equal or unequal?

Bodhi's arrow is 7 squares long and the dog's is 6. The forces on the toy are unequal.

They are unequal, and this time Bodhi's pull is the stronger one.