题目

---Which do you prefer, paper books or e-books?         ---My parents only allow me to read paper books. They _______ my eyes. A. talked about         B. have heard aboutC. are learning about  D. worry about 答案：D去南极进行科学考察，最好的季节应是北半球的:A. 秋季 B. 冬季 C. 春季 D. 夏季