This problem is very difficult.

It's difficult to collect character tiles in mahjong.

I like to play mahjong with my friends on weekends.

The child was playing in the park.

We need to gather the resources necessary to make the project successful.

We were able to gather everyone.

This picture is being sold for ten thousand yen.

Mr. Wan is my best friend.

Mr. Wan is my best friend.

Man is my best friend.