For

Preposition

introduces a complement of interest

beneficiary

-Who did you buy it for? -I bought it for her.

• For many people, the financial crisis of 2008 was truly a shock.

goal / end

• We headed for home. // We're headed for a rude awakening.
• They made off for the woods.
• We're hoping for the best.
• I don't want for them to come. ("for" is dialectal, but widespread)

What should I get her for her birthday?

Purpose

• What would you use it for?
• What did you do that for?
• Romeo, Romeo wherefore art thou Romeo?

Introduces agent in Infinitivals

• It's unusual for her to complain // For her to complain is unusual.

Conjunction

similar syntactically and semantically to car, and semantically similar to puisque (subordinating conjunction)

see the Beatitudes for some further examples.

Its use alone as a conjunction (not found before 12c.) probably is a shortening of common Old English phrases such as for þon þy "therefore," literally "for the (reason) that."

-Online Etymology dictionary [1]</i></blockquote]

• Blessed are the meek, for they shall inherit the earth.

• Romeo, Romeo wherefore art thou Romeo?

Idioms

• To stand for (1). I won't stand for it! (I won't put up with it.)
• To stand for (2).

Derived words

for and fore adverb were differentiated in Middle English

aforementioned before therefore wherefore

unrelated prefix

for- from Germanic vor- (privative)