私はどうして真夜中にあなたの家に行かなくてはいけないのかわからない。

I; me; private affairs; personal matter; secrecy; selfishness

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

why?; for what reason; how; in what way; for what purpose; what for

dead of night; midnight

at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although

you (referring to someone of equal or lower status); dear (what a wife calls a husband)

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

house; residence; dwelling; family; household; lineage; family name

to go; to move (in a direction or towards a specific location); to head (towards); to be transported (towards); to reach; to proceed; to take place; to pass through; to come and go; to walk; to die; to pass away; to do (in a specific way); to stream; to flow; to continue; to have an orgasm; to come; to cum; to trip; to get high; to have a drug-induced hallucination

if ... then; when; and; why don't you...?; the more (one does something); because; since

indicates a question (sometimes rhetorical); or; whether or not; some- (e.g. something, someone); indicates doubt, uncertainty, etc.; emphatic prefix; suffix forming adjectives or adverbs; in that way

to understand; to comprehend; to grasp; to see; to get; to follow; to become clear; to be known; to be discovered; to be realized; to be realised; to be found out