He is an expert in paleozoology and has a deep knowledge about the ecology of dinosaurs.

He decided to lose weight for his health.

He exercises every day to become thin.

He thought he was smart, but he remembered the proverb 'a fool may give a wise man council', and understood the importance of listening to others' opinions.

My friend came from Ivory Coast.

He is learning Cornish.

The International Monetary Fund is aiming for the stability of the world economy.

He used a corkscrew to open the wine bottle.

He is studying the history of National Socialism.

Understanding the concept of 'Ha-line conversion sounds' is important in learning Japanese.