Task: Question Generation
Input (English): Passage: Another factor in the revolt of 1381 was the conduct of the war with France. In 1337 Edward III of England had pressed his claims to the French throne, beginning a long-running conflict that became known as the Hundred Years' War. Edward had initial successes, but his campaigns were not decisive. Charles V of France became more active in the conflict after 1369, taking advantage of his country's greater economic strength to commence cross-Channel raids on England. By the 1370s, England's armies on the continent were under huge military and financial pressure; the garrisons in Calais and Brest alone, for example, were costing £36,000 a year to maintain, while military expeditions could consume £50,000 in only six months. Edward died in 1377, leaving the throne to his grandson, Richard II, then only ten years old.
Output (English): How many years before the revolt of 1381 did Charles V of France become more active in the conflict?