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

He knows nothing about that one case.

One part is important.

He read the Thousand and One Nights and was drawn to the charm of the Orient.

What is your answer?

He said, 'Each person has one life, like a pike or a shrimp,' and decided to live his life with care.

He likes to be formal at meetings.

He always interacts with me without standing on ceremony, in a natural way.

That is one of the formal nouns.

He is good at composing music in sonata form.