The initial tunnels were just the surface of the ground. People were transported in carriages, which were the narrow tunnels by steam engines.
A. under, broken through
B. below, put through
C. of , gone through
D. beneath, pulled through
网友回答
A. under, broken through
B. below, put through
C. of , gone through
(答案→)D. beneath, pulled through
解析：考察介词辨析和动词短语辨析。Under在…正下面（不接触）；below在水平下方；beneath在…下面（有接触面）;break through突破；put through完成，经历；go through浏览；经历；pull through渡过；经过；句意：最初的隧道就在地面的下方。人们坐在车厢里被运输，使用蒸汽机经过狭窄的隧道。根据句意什么名字D正确。