Inventions and creations refer to scientific researchers working on the basis of practice () and obtaining results that have not been obtained before and have certain uses.

A、toexploreareasthatarenotpreviouslyexplored
B、tocarryoutworkthathasnotbeendonebefore
C、tosolveproblemsthathavenotbeensolvedbypreviouspeople
D、tocompletetasksthatarenotpreviouslycompleted