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Update more-morphisms.tex

Thanks to Yijin Wang  https://stacks.math.columbia.edu/tag/03GW#comment-7352

Typo in the proof of lemma 37.42.1: in the beginning， (b) should be U=f’^｛-1｝（U’）

Try to use L/K notation for field extensions

We could also try to consistenly use "field extension" and not just
"extension" and consistently use "ring extension", etc.

pell check: words starting with n, o, p, q, r, N, O, P, Q, or R

Towards ZMT for spaces

Bunch of changes, crystallizing some earlier results

This commit adds:
(1) Relative dimension of a flat morphism can be read off from
what happens over a dense open
(2) Characterizing open immersions as flat morphisms which induce
an isomorphism over a dense open
(3) Finite type, flat, and finitely presented over a dense open
implies finitely presented
(4) Proper modifications can be dominated by blowups

Typo

End conversion of etale to \'etale.

Started to use ew terminology

	"elementary etale neighbourhoods"

Tags: Added new tags

More on Morphisms: Improved discussion on quasi-finite morphisms

	Now we use the material on normalization (in Morphisms) which
	was not available in the first pass on the structure of
	quasi-finite separated morphisms. In particular, using the fact
	that normalization commutes with etale base change improves the
	exposition and clarifies the proof. Not only that, it also gives
	a slightly more general result, namely, we do nnot even have to
	assume the morphism is quasi-finite at all. Just finite type and
	separated.

	Future addition: It seems quite possible that given a proper f :
	X --> S with S qc+qs then the normalization of S in X is just
	the spectrum of f_*O_X and moreover the fibres of the map to
	this normalization are connected. In other words, the connected
	fibres thing holds without assuming the base is Noetherian. It
	should be possible to prove this using the results on limits of
	schemes.

	modified:   more-morphisms.tex