He tripped over the pebble at his feet.

He picked up a stone and threw it.

Harry was searching for the Philosopher's Stone.

His strong will led him to success.

His intention was clear.

A neutron is part of an atomic nucleus.

Neutron stars are known for their density and strong gravity.

He is as stubborn as a head as hard as a stone.

This soil is lacking in lime, so it is necessary to add lime.

He works digging out coal.