Complex sentence: Reinforcements from the reserve brigade and an extra battalion reached Beaucourt and extended the position to the left as far as Beaucourt Alley by, two battalions reached the first objective by midnight and a battalion took over the British front line.
Split into simpler sentences: Reinforcements from the reserve brigade and an extra battalion reached Beaucourt and extended the position to the left as far as Beaucourt Alley by. Two battalions reached the first objective by midnight and a battalion took over the British front line.