例句與造句

1. More precisely, let X be a smooth morphism from X to another smooth projective surface Y such that the curve C has been contracted to one point P, and moreover this morphism is an isomorphism outside C ( i . e ., X \ setminus C is isomorphic with Y \ setminus P ).
2. It's difficult to find surface y in a sentence. 用surface y造句挺難的