Since that's his own concern, we better not interfere.

He should stop his selfish behavior.

He lost everything.

She is planning a date with her current boyfriend.

My boyfriend gave me a gift.

Everyone was surprised by the news.

He is an expert in comparative linguistics.

He is world-famous as a comparative linguist.

He starts talking about himself at every opportunity, causing trouble for the people around him.

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