Complex sentence: While the Portuguese fleet bombarded enemy positions on shore, the infantry rowed the crafts onto the beaches on either side of the city's bridge, immediately coming under artillery fire from the Malayan stockades, though it was largely ineffective.
Split into simpler sentences: While the Portuguese fleet bombarded enemy positions on shore, the infantry rowed their boats onto the beaches on either side of the city's bridge. They immediately came under artillery fire from the Malayan stockades, though it was largely ineffective.