He used stepping stones to cross the river.

The mist is covering the mountain.

He is always hanging out with bad friends. Truly, birds of a feather flock together.

He tripped over the pebble at his feet.

He picked up a stone and threw it.

Harry was searching for the Philosopher's Stone.

My father is an excellent doctor.

His strong will led him to success.

His intention was clear.

A neutron is part of an atomic nucleus.