He studied the teachings of Buddhism deeply to understand the meaning of 'two traveling together'.

He enjoys derivative works of anime.

Nitrogen dioxide is a cause of air pollution.

He commutes by two-wheeled vehicle.

Fujiko is my best friend.

His speech was a double negative, making it difficult to understand.

Nikaido-san is my best friend.

The Second International was established to protect the rights of workers.

Where will the second party be held?

Solving a quadratic equation is difficult.