。
She was drunk.
Literal
She [topic-は] was-drunk.
酔っていた uses the ~ていた form of 酔う (よう, to get drunk) — marking the resulting state: she had become drunk and was in that state. A minimal, unadorned statement. 酔う also works for other kinds of intoxication: 船に酔う (get seasick), 車に酔う (get carsick).