sentence: Banks was to clear the Shenandoah Valley of Confederate forces, then move up towards Washington so McDowell's force of 30,000 could move against Richmond from the north.
modified: fix grammar: Bank was to clear the Shenandoahs Valleys of Confederate force, then move up towards Washingtons so McDowells's forces of 30,000 could move against Richmonds from the norths.