The absent voters list shows Frederick Thomas Gates of West End, Stanwick as a Private in the "1st H.L.I.". Normally this would be interpreted as the 1st Battalion Highland Light Infantry (an infantry unit on the Western Front during 1915 and later in Mesopotamia).
However, there is no medal card for Frederick Gates under that number - which would mean that either the card is lost, he didn't serve overseas or that he was transferred to a different Regiment before serving overseas.
Steve.