The human immunodeficiency virus is the virus that causes AIDS.

I read the Letter to the Ephesians and gained a deep understanding of Christian teachings.

We are here to solve that problem.

I like memorizing the Hyakunin Isshu.

It's difficult to memorize the Hyakunin Isshu.

He is studying the history of African Americans.

They have a variety of opinions, making it difficult to agree.

He is recognized as the top person in that field.

Zoonosis is a disease that spreads from animals to humans, or vice versa.

In order to solve problems, it is important to listen to the opinions of many people, as the saying goes, 'two heads are better than one'.