Complex sentence: Intended to only be a temporary wartime measure through the remainder of World War One, This new law required all hotel bars to close at 6pm nightly (and all day Sunday) It was made permanent in 1919 owing to pressure from the then powerful temperance movement.
Split into simpler sentences: Intended to only be a temporary wartime measure through the remainder of World War One, this new law required all hotel bars to close at 6pm nightly (and all day Sunday). The Swill was made permanent in 1919 owing to pressure from the then powerful temperance movement.