He is recognized as the top person in that field.

The human immunodeficiency virus is the virus that causes AIDS.

When he had a problem due to his own actions, he remembered the phrase 'chickens come home to roost'.

He is collecting centime, the old currency of France.

I want to go to Saint Barthélemy.

Essential amino acids are necessary to be taken from our diet because our body cannot produce them on its own.

Essential amino acids, which the human body cannot produce on its own, need to be obtained from the diet.

I am a member of the Third International.

Hydrocyanic acid is a very dangerous chemical.

As soon as he arrived, he said 'I just got here.'