Simplify the following text for a Grade 8 native English-speaking person.
Original: Saint-Vaast-sur-Seulles is a commune in the Calvados department in the Basse-Normandie region in northwestern France .
Simplified: Saint-Vaast-sur-Seulles is a commune . It is found in the region Basse-Normandie in the Calvados department in the northwest of France .