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.
Q: A flag carrier is an airline or ship line that is owned by the government of the country it is based in .
A: 
A flag carrier is a transportation company , such as an airline or shipping company , that , being locally registered in a given sovereign state , enjoys preferential rights or privileges accorded by the government for international operations .