long period

Another issue is the process of demining once a conflict is over, and clearing land that has been mined can take a long period of time.

The sequence of building blocks has evolved over a long period of time; we all inherit them from our parents.

Climate is the pattern of the weather conditions over a long period of time for a large area.

The presence of Bes mugs in different contexts over a long period of time made it extremely difficult to speculate on their contents or roles in ancient Egyptian culture.

She said "significant errors" made by the hospital and the fact these were undetected for such a long period of time were are "evidence of substandard care and systemic failure".