Ryoko is my best friend.

It's hard to say, but I think you're wrong.

He always used to say, 'It's easy to say, but hard to do.'

He is good at expressing his feelings well.

This book is very good.

Infrared astronomy provides a new perspective on understanding the universe.

He is an expert in human anatomy.

The house sold for a good price.

He emphasized that there is still much to do, saying 'It's a long road ahead as the sun sets.'

Katori is my best friend.