In the images, you see all kinds of possible defense constructions to hold back the Romans, Germans, Vikings, and now nature as enemy number one.
2017年6月六级真题（第二套）听力 Section A
The area's ship building tradition, partly established by the Vikings, also meant that sophisticated carpentry was a major aspect of the local culture.
2019年12月六级真题（第一套）听力 Section C
柯林斯高阶英汉双解学习词典释义
N-COUNT
（8至11世纪的）北欧海盗
The Vikings were men who sailed from Scandinavia and attacked villages in most parts of north-western Europe from the 8th to the 11th centuries.