Complex sentence: Wilson commanded the 5th Infantry Brigade of the British Army during the campaign to liberate the Falkland Islands after their seizure by the Argentinian Armed Forces, in conjunction with the Royal Marines' 3rd Commando Brigade, commanded by the then Brigadier Julian Thompson.
Split into simpler sentences: Wilson commanded the 5th Infantry Brigade of the British Army during the campaign to liberate the Falkland Islands after their seizure by the Argentinian Armed Forces. The second major unit was the Royal Marines' 3rd Commando Brigade, commanded by the then Brigadier Julian Thompson.