题目

---Why do you suggest Gulin? ---I believe_____ beauty of ____ nature there will make _____ excellent impression upon the tourists. A. a, the, an    B. the, the, an     C. the, /, the     D. the, /, an 答案：D 解析: the beauty of natural指“自然美景”， make an excellent impression upon sb.表示“给某人留下良好的印象”。18、 I didn’t manage to work out the problem        the teacher had explained how. A. until                         B. unless               C. when                       D. before