单语范例（未经PONS编辑处理）
A broad, low-level circulation center had formed within the system and became increasingly organized, showing signs of developing convective banding.
en.wikipedia.org Reconnaissance aircraft reports indicated the system initially lacked a circulation.
en.wikipedia.org Ship reports revealed a closed circulation, though the center was elongated in a northwestsoutheast oriented manner.
en.wikipedia.org The first newspaper in the state started circulation herein 1825.
en.wikipedia.org There were at least seven private weekly publications with circulation in the low thousands.
en.wikipedia.org