To some, the twin towers looked like two big boxes.
To some 可以看作是To some people 的省略:
对一些人来说,双子塔看起来像两个大盒子。
又如:To some, this appeal for a form of neo-populism will no doubt seem naive. 对一些人来说,这种对新民粹主义的一种形式的要求无疑显得很幼稚。