In the time of; as long as the action or existence of; as, during life; during the space of a year
If something happens during a period of time or an event, it happens continuously, or happens several times between the beginning and end of that period or event. Sandstorms are common during the Saudi Arabian winter
If something develops during a period of time, it develops gradually from the beginning to the end of that period. Wages have fallen by more than twenty percent during the past two months
An event that happens during a period of time happens at some point or moment in that period. During his visit, the Pope will also bless the new hospital