Complex sentence: To the north the 5e DLC got in position unchallenged and by evening, the Belgian Chasseurs Ardennais in front retired northwards and on the Ninth Army front, fought a delaying action at Chabrehez.
Split into simpler sentences: To the north the 5e DLC got in position unchallenged. By evening the Belgian Chasseurs Ardennais in front retired to the north and on the Ninth Army front fought a delaying action at Chabrehez.