27 steel construction, buildings could then have a great many stories.
答案：(C) With
With 表示「藉由／有了……」，With steel construction（有了鋼構工法）符合「因為有這項技術，建築物才能蓋很多層樓」的因果邏輯。In／For／Beside 都無法表達這種「憑藉某條件」的語意。
四個選項都是單字介系詞，形態上都放得進去，你會憑中文挑一個。
答對率不到五成，鑑別度高達 55。空格後面是 steel construction（鋼構工法），一個名詞組；主要子句是 buildings could then have a great many stories（建築物於是能蓋很多層）。兩者的關係是「有了前者，才有後者」——有了鋼構工法，樓才蓋得高。表示「有了……」用 With。填進去讀成 With steel construction, buildings could then have a great many stories。還有一個看得見的印證：主要子句裡的 then（於是、那時候）正好呼應 With 帶出來的那個前提。
In（在……之中）後面接的是空間或範圍；For（為了；因為）帶出的是目的或原因，但鋼構工法不是蓋高樓的目的；Beside（在……旁邊）講的是位置。三個都是介系詞，形態吻合，容易被順手選走。
with ＋ 名詞（有了……）、without ＋ 名詞（沒有……）、a great many ＋ 複數名詞（許多的）、story（樓層；故事）、construction（建造、工法）、beside（在……旁邊）。
Science makes possible the use of new materials and new methods of producing objects. For example, some 20th-century chairs are made of steel and plastic. These materials, 24, were undreamed of in the 18th century. As new materials develop, one invention often 25 another.
Steel, for instance, was developed by engineers in the 19th century. 26 its strength, steel soon became a useful building material. 27 steel construction, buildings could then have a great many stories. But no one could be expected to walk up 8, 10, or 30 flights of 28.
Therefore, to make tall buildings more accessible to their users, the elevator 29. By providing much-needed space in a world 30 people, tall buildings have solved a great problem of the city and have completely changed our way of life.