Teacher:In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.
Teacher: Now, understand the problem? Solve this instance: The palace was a papal residence until 1870 .
Student:
It served as a papal residence and housed the central offices responsible for the civil government of the Papal States until 1870 .