例句與造句

1. In 1951 , h . hopf proved , by associating a holomorphic 2 - differential to each constant mean curvature surfaces in r3 , that only compact genus zero surfaces immersed in r3 with constant mean curvature are the round sphere , in chapter two , we consider the same question about the compact 2 - type surfaces of genus zero in s7
   1951年， h . hopf發(fā)現(xiàn)r ~ 3中每個(gè)常平均曲率曲面都伴隨一個(gè)全純微分2 -形式，并證明了零虧格的常平均曲率閉曲面一定是r3中的球面.本文的第二章對(duì)于獷中零虧格的2型曲面討論了類(lèi)似的問(wèn)題
2. It's difficult to find zero surface in a sentence. 用zero surface造句挺難的