He tripped over the pebble at his feet.

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.

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.