He was observing the stars with a telescope.

In physics class, I learned about the properties of convex mirrors.

He conducted an experiment using a spherical lens.

The speculum of this bird has a very beautiful color.

This magic mirror came from China.

He is good at reading mirror writing.

The bird called Ruanjing that appears in Chinese mythology is known for its beautiful appearance.

His behavior is like a mirror image of his father.

I use a microscope for biology experiments.

He was observing the distant birds with binoculars.