可数覆盖

The text applies the covering theory to the study and discussion of the relative compact, the relative countably compact and the relative Lindelff compact.

运用覆盖理论，对相对紧、相对可数紧和相对Lindelff紧进行研究和讨论，给出了它们之间的一些关系，并且结合相对分离性，获得某些传递等性质。

The theory of generalized metric properties and covering properties stems from a generalization of metrizability and compactness, in which a great many problems involve a research for certain point-countable covers.

作为对可度量性与紧性一般化而形成的广义度量理论与覆盖性质理论中的许多问题涉及到对确定的点可数。。。

In chapter 2, we prove that sn—first countable spaces are preserved by the finite subsequence-covering mappings.By this result, we prove that the finite subsequence-covering, quotient mappings preserve g—metrizable spaces, also prove that the finite subsequence-covering, closed mappings preserve sn—metrizable spaces, g-metrizable spaces, metrizable spaces, point-countable bases.

在第二章中，我们主要证明了有限子序列覆盖映射保持sn-第一可数空间，作为它的应用，又证明了有限子序列覆盖、商映射保持g-第一可数空间，也证明了有限子序列覆盖闭映射保持sn-度量空间，g-度量空间，度量空间，点可数基。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。