地下火的英文：
ground fire

参考例句：

When you' re standing in the subway, you' d better hold on to the strap
当你站在地下火车上时，你最好抓住皮环。

ground是什么意思：
n. 地面，土地
v. 着陆， 打基础
adj. 磨平的，磨碎的

on solid ground
在稳固的基础上

Their ship was grounded.
他们的船搁浅了。

The ground has thawed.
地面解冻了。

The beans are then ground and packaged for sale as ground coffee.
然后那些咖啡豆被磨碎，包装好作为咖啡粉出售。

He was lying flat on the ground.
他平躺在地上。

fire是什么意思：
n. 火；炉火；火灾；热情；激情；磨难；炮火
v. 点燃；烧制；烘制；激励；充满激情；解雇；着火；开枪

The fire raged.
大火熊熊燃烧。

They fired at the robbers.
他们向强盗开枪。

The house was on fire.
房子起火了！

paid fire brigade= professional fire brigade
支取薪金的消防队

Fires beaconed the darkness.
火光驱散了黑暗。