1.24 demonstrate an understanding of Newton’s third law

Most commonly put a 'each force has an equal and opposite force' the principle of this law is that two bodies interacting are both exerting a force on each other.

The most simple example of this is that when you sit on a chair you are exerting a downward force on the chair, but the chair is also pushing back up at you (or you would be sinking into the ground.) Another example is that when you swim you push the water backwards which pushes you forward.