。
She got married last year.
Literal
She [topic-は] last-year married.
A bare statement — no partner mentioned, no ceremony detail, just the fact of marriage and its timing. 結婚する on its own is grammatically complete; the partner phrase ~と is optional and gets dropped when context already provides it or when the speaker doesn't want to specify. This kind of omission is typical of Japanese, which tends to leave out anything not communicatively necessary. The subject 彼女 ('she') is the topic, and even the time particle is bare: 去年 floats as an adverbial without に, the way most relative-time words do.