間違えたからと言って彼をあざ笑うな。

to make a mistake (in); to commit an error (e.g. in calculation); to confuse; to mistake something for something else

from (e.g. time, place, numerical quantity); since; from (originator); by; because; since; out of (constituent, part); through (e.g. window, vestibule); after; since

if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)

to say; to utter; to declare; to name; to call; to go (e.g. "the alarm went ping"); to make a noise

he; him; his; boyfriend

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to sneer at; to ridicule

(sentence end, mainly masc.) indicates emotion or emphasis; (used with masu stem verb) command; (used with dictionary form verb) prohibition