Complex sentence: By the time of the D Day landings the commando had lost the Yugoslav, Polish troops and the two French troops were attached to No.4 Commando in the 1st Special Service Brigade and landed on Sword Beach.
Split into simpler sentences: By the time of the D Day landings the commando had lost the Yugoslav, Polish and the two French troops. The two French troops were attached to No.4 Commando in the 1st Special Service Brigade and landed on Sword Beach.