あなたはインクで名前を書かなければなりません。

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

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

ink

indicates location of action; at; in; indicates time of action; indicates means of action; cause of effect; by; and then; so; indicates continuing action; indicates certainty, emphasis, etc.

name; full name; given name; first name

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 write; to compose; to pen; to draw; to paint