He became good at playing the piano, and finally acquired the skill.

He was so ashamed of his failure that he wished he could crawl into a hole.

Due to the earthquake, cracks appeared in the wall.

This information sank in immediately.

His cooking skills are among the top five in the local area.

"Once in a lifetime" means to cherish the encounter that happens only once in one's lifetime.

He missed a once-in-a-lifetime opportunity.

The story of the time of creation is mysterious and interesting.

What is the half-life of this substance?

A new school term is starting.