As the Heian period progressed, however, the kokushi provincial governors came to exert military power independent of the central government in Kyoto.

As the Late Classic period progressed, obsidian became increasingly accessible to the lower classes of Maya civilization.

This first period ends in 3000BC and then progresses to the Archaic period.

As the industrial period progressed however, this view began to be replaced by a more economic oriented approach.

Gondwana started the period in equatorial latitudes and, as the period progressed, drifted toward the South Pole.

As the period progressed however, the dominance of the cavalry elite began to slowly break down.

Pitino sent Sidney Green into the game and ordered his team into a full-pressure defense, which he changed several times as the second period progressed.

The Devils became gradually better as the third period progressed and scored the last two goals.

Yew, the primary stave making material for the European longbow, became scarcer as the medieval period progressed.

As this period progresses the quality and craftmanship of ceramics deteriorates.