Please infer the content of the blank from the context before and after the sentence.

I am studying Japanese.

I attended the party as a chaperon for my younger sister.

A pleasant chat with friends is always enjoyable.

I had a pleasant chat with my friend at the coffee shop.

He transports people every day by rickshaw.

Mokuzen-san is always a quiet and calm person.

His success is right before his eyes.

He left the room in silence.

He doesn't understand the situation in front and behind.