반응형 고1 영어 이재영1 고1 천재 이재영 5과 본문 Keystones in Nature 읽기 연습 Lesson 5 Our Earth, Our Future, Our Choice Keystones in Nature Host: Welcome to Student Science Show. Today, we'll be discussing an important topic―keystone species, and our special guest is an expert on ecosystems and the environment. Dr. Walters, welcome! Dr. Walters: It's my pleasure to be here. Host: Dr. Walters, let's get right to the point. What exactly is a keystone species? Dr. Walters: .. 이전 1 다음 반응형