题目

从沿海向内陆，各种自然带的逐渐替代较为明显的是                A.中高纬度     B.中低纬度        C.中纬度        D.低纬度   答案：C   18.Seldom ____ him recently， for you see I’m preparing for the project. A. I meet        B. do I meet         C. I have met            D. have I met