Complex sentence: The 3rd Greek Battalion advanced up the left through the hedges and ditches beyond Caselecchio until they came level with the 1st Greek Battalion in the centre, their task was made difficult as they had to occasionally clear minefields and were under constant fire.
Split into simpler sentences: The 3rd Greek Battalion advanced up the left through the hedges and ditches beyond Casalecchio until they came level with the 1st Greek Battalion in the centre. Their task was made difficult as they had to occasionally clear minefields and were under constant fire.