And according to satellite pictures published two years ago, on the far side of a peninsula that juts into the bay lie the cavernous entrances to a vast underground submarine base.

两年前发布的卫星照片显示，在伸入海湾的半岛远端，还坐落着一座洞窟似的入口，通往巨大的地下潜艇基地。

youdao

A carefully selected asteroid with the right density and strength could be hollowed out for an underground base to be established.

一个精心挑选合适的小行星密度和力量可以挖了一个地下基地。

youdao

The 95.3-mile (153.5 km) long Gotthard Base tunnel network now being drilled out beneath the Alps, when finally completed in about ten years, will be the longest underground tunnel ever constructed.

目前正在阿尔卑斯山脚开凿的圣哥达隧道网长95.3英里(153.5公里)，将在10年以后完工，也将是有史以来最长的地下隧道。

youdao

On Hainan Island it has built a new, large naval base with underground submarine pens, which can support both strategic and nuclear-attack submarines.

CENTERFORSECURITYPOLICY: Enter the dragon

At the base, they find large areas of the underground mall still standing as they were the morning of September 11, nearly untouched.

CNN: workers

Since tax evasion is a major driver of the underground economy, efforts to expand the tax base and improve tax collection can help curtail illicit flows, says Kar.

FORBES: India Has Lost At Least A Half-Trillion Dollars To Corruption Since Independence