The shape of this crystal lattice is very unique.

He has difficulty expressing his emotions in words.

He showed his gratitude on his face.

This concept is difficult.

He was looking outside through the lattice window.

A phonon is a physical concept that represents the vibration of a crystal lattice.

This machine has intense oscillations, so please use it with caution.

This machine oscillates at a constant frequency.

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

This crystal has a very beautiful shape.