Black Friday: lifetime access is on a special offer in the app, until November 30. Black Friday: special offer on lifetime access, until November 30. Download
생물학적 다양성은 생태계의 건강을 유지하는 데 중요하다.saengmulhakjeok dayangseong-eun saengtaegye-ui geongang-eul yujihaneun de jungyohada.Biological diversity is important for maintaining the health of ecosystems.