This project is focused on a single goal.

He doesn't waste even a single grain of rice.

He knows nothing about that one case.

I saw a dog in the park.

I saw one dog in the park.

He ate a slice of bread.

This timber has a length of one shaku and one sun.

In ancient China, shaku was an important unit.

The capacity of this bottle is one koku.

He picked up a fig and gently peeled off the skin.