彼は私の頭をたたいた。

he; him; his; boyfriend

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

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

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

head; hair (on one's head); mind; brains; intellect; leader; chief; boss; captain; top; tip; beginning; start; head; person; top structural component of a kanji

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 strike; to clap; to knock; to dust; to beat; to play drums; to abuse; to flame (e.g. on the Internet); to insult; to use up money; to call; to invoke (e.g. a function)