OG2020语法分册 of up to用法求解

sharon0119

求大神讲解一下of up to的用法，之前只接触过up to的用法。
The Anasazi settlements at Chaco Canyon were built on a spectacular scale, with more than 75 carefully engineered structures, of up to 600 rooms each, were connected by a complex regional system of roads.

• Ascale, with more than 75 carefully engineered structures, of up to 600 rooms each, were 分析该选项
• Bscale, with more than 75 carefully engineered structures, of up to 600 rooms each, 分析该选项
• Cscale of more than 75 carefully engineered structures of up to 600 rooms, each that had been 分析该选项
• Dscale of more than 75 carefully engineered structures of up to 600 rooms and with each 分析该选项
• Escale of more than 75 carefully engineered structures of up to 600 rooms each had been
  

求问OF UP TO的用法

wu0h961738

樓主對這題的誤解應該是沒察覺到of up to 600 rooms each是作為插入句。
修飾每個engineered structures 最多(up to)有六百間。

其他相對選項在句子結構上就有很多錯誤，也不符合我們要討論的問題，便不再昝述。