bracket multiplication

例句：

1. 1. The book is bracketed by two large windows.
   这本书被两扇大窗户包围。
2. 2. The artist used a variety of materials to create the bracket.
   艺术家使用各种材料来创作这个框架。
3. 3. The construction was completed within the specified bracket.
   建筑在规定的框架内完成。