He suffered a fracture of the lesser trochanter.

He fractured his greater trochanter.

The theory of harmonic oscillators is a fundamental concept in physics.

His father was very stubborn, so the proverb 'Like father, like son' fits perfectly.

She's always a goody two shoes, and is well-liked by her teachers.

Yuriko is my best friend.

I found a rare seahorse in the sea.

I found a seahorse in the sea.

The crowned seahorse is one of the most beautiful creatures in the sea.

The hawthorn tree bears beautiful fruits in the fall.