Looking at the bird flying high in the sky, I felt freedom.

In mathematics, an empty set refers to a set that does not contain any elements.

He made a fake snore to pretend to be asleep.

The doctor said there is a problem with his jejunum.

I am enjoying cherry blossom viewing under the spring sky.

I enjoyed a picnic under the summer sky.

He likes to take a walk in the park at dusk.

He was fascinated by the beauty of the dragonfly.

He was appointed as an air commodore.

He was promoted to the rank of Second Lieutenant in the Air Force last year.