Sentence:  Nothing could be more business-like than the construction of the stout dams, and nothing more gently rural than the limpid lakes, with the grand old forest trees marshalled round their margins like a <WSD>veteran</WSD> army that had marched down to drink, only to be stricken motionless at the water's edge. 
Meaning of the word marked with <WSD> tags:  Having had long experience, practice, or service.