A German 88mm gun abandoned near the coast road, west of El Alamein, Egypt, North Africa; 7 November 1942.

Gun left behind in retreat

Men of the 7th Seaforth Highlanders, 15th Scottish Division, keep an eye out for snipers from a ruined building in Uelzen, 18 April 1945
This is the caption but I guess that soldiers watching for snipers wouldn't give themselves away as targets like this ;)
taken from fb/Bren LMG owners club

Watching for...

Troops of the British Army and French Air Force sitting outside a dugout in November 1939 during the 'Phoney War'.Note the Lewis gun (.303)  in AA configuration.
taken from fb/History of WW2