Your design主语 approximates及物动词 what I understood the building would be like宾语从句
这个宾语从句是一个嵌入式名词性关系分句。what=the thing which。即从句等于 the thing which I understood the building would be like . 这样，关系代词which在I understood的宾语从句中作介词like的宾语。如果网友不太了解嵌入式关系分句，可在本网搜索有关解答。
