例句與造句

1. The unitary group " U " in Bott's sense has a classifying space " BU " for complex vector bundles ( see Classifying space for U ( n ) ).
2. Thus U ( \ mathcal H ) is a contractible space with a U ( 1 ) action, which identifies it as EU ( 1 ) and the space of U ( 1 ) orbits as BU ( 1 ), the classifying space for U ( 1 ).
3. It's difficult to find classifying space for u in a sentence. 用classifying space for u造句挺難的