The Mark IV was first used in mid 1917 at the Battle of Messines Ridge. They remained in service to the end of the war.
The Mark IV was first used in large numbers on 7 June 1917, during the British assault on Messines Ridge. Crossing dry but heavily cratered terrain, many of the sixty-plus Mark IVs lagged behind the infantry, but several made important contributions to the battle. By comparison, at the Third Battle of Ypres (also known as Passchendaele) from 31 July, where the preliminary 24-day long barrage had destroyed all drainage and heavy rain had soaked the field, the tanks found it heavy going and contributed little; those that sank into the swampy ground were immobilized and became easy targets for enemy artillery.
Nearly 460 Mark IV tanks were used during the Battle of Cambrai in November 1917, showing that a large concentration of tanks could quickly overcome even the most sophisticated trench systems.
In the aftermath of the German Spring Offensive on the western front, the first tank-to-tank battle was between Mk IV tanks and German A7Vs in the Second Battle of Villers-Bretonneux in April 1918.
About 40 captured Mark IVs were employed by the Germans as Beutepanzerwagen (The German word Beute means "loot" or "booty") with a crew of twelve. These formed four tank companies from December 1917. Some of these had their six pounders replaced by a German equivalent.
The last Mark IV to see service was Excellent, a Mark IV male retained by the naval gunnery school on Whale Island, HMS Excellent. In the early years of the Second World War it was restored to operational status and driven to the mainland, where its new career was allegedly brought to an early end after a number of cars were damaged.
In the internet I found a printable plan of a papermodel of the Mark IV Tank. Some added details with woodglue and wire are nessesary and not too much work - I did it while watching TV. It is a very easy kit and looks - painted with email-colours - very fine and authentical. Friends told me that there is not much difference to a plastic-model. In future times it will be a part of a big WWI-diorama which will be placed in the Automuseum Melle.