1
I accidentally broke my favorite mug.
Sign 'broke' by mimicking the snapping motion, then point to yourself and sign 'mug' to explain what happened. A surprised facial expression works perfectly here to show it was an accident.
2
Be careful, that chair is broken.
Use the sign for 'broke' to indicate the chair's condition, making the snapping motion clear and deliberate. You can point to the chair first to establish what you are talking about.
3
He broke the pencil in half.
Show the 'broke' sign with a sharp, crisp movement to emphasize the sudden snapping of the pencil. The 'S' handshapes perfectly represent holding the small wooden object before it snaps.