Complex sentence: She married Captain David Duffy who served in the Honourable Artillery Company later Royal Artillery in Germany and travelled extensively to France, Italy, Austria and Denmark, and after spending a year in Spain and back in England, moved with him to the USA in 1978.
Split into simpler sentences: She married Captain David Duffy, who served in the Honourable Artillery Company, later Royal Artillery, in Germany and travelled extensively to France, Italy, Austria and Denmark. After spending a year in Spain and back in England, she moved with him to the United States in 1978.