Offspring of a/o shapes

There are some words in the English tung which in the bygone were written with either a or o. It is often said that o shapes stem from the south, whereas a shapes stem from the north. While this calls for a more in-depth look, the following is only a short rundown of what became of a and o shapes later. May it be of some help to settle on the nowaday shape of a word of old when it is brought back.

-f

a
o	of(f)

-ld

a
o	bold	cold	fold	hold	old	wold

-m

a		ham	ram	sam (verb)
o	from

-mb

a		lamb
o	comb		womb

-me

a	game	lame	name	shame	tame
o

-n

a	ban (verb)	can (verb)	man		pan (WG < L)	span	swan	than	wan (adj.)
o				on

Hark that on, swan, and wan share the same loud in many a bytung of English, but only one is written with an o.

-nd

a	and	band	brand	hand	land	sand	stand	strand 'beach'
o		bond

-ng

a		fang	gang	hang		pang		stang (< ON)		tang 'point, tip' (< ON)	whang
o	among				long	prong	song		strong		thong	throng	tongs	wrong (< ON)

For there is no sheer overweight of words with either a or o shapes, it is best to look at each word to be brought back on its own. Headwords of wordbooks can give some hint as to how to write them.

-t

a	want 'mole'
o