In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Q: Passage: John Douglas (11 April 1830 – 23 May 1911) was an English architect who designed over 500 buildings in Cheshire, North Wales, and northwest England, in particular in the estate of Eaton Hall. He was trained in Lancaster and practised throughout his career from an office in Chester. Initially he ran the practice on his own, but from 1884 until two years before his death he worked in partnerships with two of his former assistants.
Douglas's output included new churches, restoring and renovating existing churches, church furnishings, new houses and alterations to existing houses, and a variety of other buildings, including shops, banks, offices, schools, memorials and public buildings. His architectural styles were eclectic. Douglas worked during the period of the Gothic Revival, and many of his works incorporate elements of the English Gothic style. He was also influenced by architectural styles from the mainland of Europe and included elements of French, German and Dutch architecture. However he is probably best remembered for his incorporation of vernacular elements in his buildings, in particular half-timbering, influenced by the black-and-white revival in Chester. Other vernacular elements he incorporated include tile-hanging, pargeting, and the use of decorative brick in diapering and the design of tall chimney stacks. Of particular importance is Douglas's use of joinery and highly detailed wood carving.
Throughout his career he attracted commissions from wealthy landowners and industrialists, especially the Grosvenor family of Eaton Hall. Most of his works have survived, particularly his churches. The city of Chester contains a number of his structures, the most admired of which are his half-timbered black-and-white buildings and Eastgate Clock. The highest concentration of his work is found in the Eaton Hall estate and the surrounding villages of Eccleston, Aldford and Pulford.
A:
What is the last name of the person whose works have mostly survived, particularly his churches?