。
The gate is closed at 6 o'clock.
Literal
Gate [topic-は] 6 o'clock [at-に] is-closed-[passive-られる].
The passive 閉められる ('be closed') — present tense here giving the habitual/scheduled reading 'is closed (as a rule).' Without the passive, the sentence would require an overt agent; the passive makes it a clean habitual.