They see the amazing powers of batteries and electrical circuits, and how they are used to power buzzers, toys, and other simple machines.
(They; see; the amazing powers of batteries and electrical circuits, and how they are used to power buzzers, toys, and other simple machines) (they; are used; to power buzzers, toys, and other simple machines)
They they
see are used
the amazing powers of batteries and electrical circuits, and how they are used to power buzzers, toys, and other simple machines
to power buzzers, toys, and other simple machines