。
When did Ms. Suzuki leave Japan?
Literal
Suzuki-teacher [topic-は] when Japan [object-を] departed [question-のですか].
たた(れ)る is the honorific/keigo reading of 立つ ('to stand, depart') — here in its honorific-respectful use for a teacher's action. The passive-form ending ~れる is regularly repurposed as a mild honorific in polite speech. 日本をたたれた = '(the honored person) departed Japan.' A subtle keigo touch.