✔ 最佳答案
How has XXX developed since 1700 : 即係要答自從 1700 之後既野 since 1700 (自從1700 之後) since 1700 = after 1700 and to the present time
How has XXX developed since 1700 = How has XXX developed after 1700 and to the present time How has XXX developed between 1700 and now