this is the correct way

A: I was attacked by a man.

B:When did that happen to you?

A:It happened yesterday.

B:With what did he attack you?

A:He attacked me with a knife.

the study of the way the sentences of a language are constructed; morphology and syntax.

the above answers corrected the use of the wrong word: mistakenly using “attached” for the word “attacked.”

mor·phol·o·gy

the patterns of word formation in a particular language, including inflection, derivation, and composition.

syntax

a.the study of the rules for the formation of grammatical sentences in a language.

b.the study of the patterns of formation of sentences and phrases from words.

my guess is “With what did he attack you”?

it is the most common usage.

B: When did he attack you?

A: He attacked me yesterday.

B: What did he attack you with?

A: He attacked me with his knife.

Hopefully thats right, if not i think i should go back to school!!!!! LOL

B: When did that happen to you?

A:The attack happened yesterday.

B: What did he attack you with?

A:He attacked me with a knife.