For

来自Big Physics

wiktionary

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From Middle English for, from Old English for(“for, on account of, for the sake of, through, because of, owing to, from, by reason of, as to, in order to”), from Proto-Germanic *furi(“for”), from Proto-Indo-European *preh₂-.

Cognate with West Frisian foar(“for”), Dutch voor(“for”), German für(“for”), Danish for(“for”), Swedish för(“for”), Norwegian for(“for”), Icelandic fyrir(“for”), Latin per(“by, through, for, by means of”) and Romance language successors (e.g. Spanish para(“for”)), Ancient Greek περί(perí, “for, about, toward”), Lithuanian per(“by, through, during”), Sanskrit परि(pári, “over, around”).


etymonline

ref

for (prep.)

Old English for "before, in the sight of, in the presence of; as far as; during, before; on account of, for the sake of; in place of, instead of," from Proto-Germanic *fur "before; in" (source also of Old Saxon furi "before," Old Frisian for, Middle Dutch vore, Dutch voor "for, before;" German für "for;" Danish for "for," før "before;" Gothic faur "for," faura "before"), from PIE root *per- (1) "forward," hence "in front of, before," etc.

From late Old English as "in favor of." For and fore differentiated gradually in Middle English. For alone as a conjunction, "because, since, for the reason that; in order that" is from late Old English, probably a shortening of common Old English phrases such as for þon þy "therefore," literally "for the (reason) that."