2，2x，x+y是整式，故A．B，C错误；
D、是分式，故选项正确．
故选D．
1t was so lucky that I came across my old friend _____ I came to this
company. [ ]
A. the first time
B. every time
C. for the first time
D. at times
峨眉山伏虎寺坐落在峡谷林海中，但屋顶从来不积存残枝落叶，这是峨眉山一大奇观，为什么？康熙皇帝为此题写了哪三个字？
