underground

/ˈəndərˌgraʊnd/

a secret group organized to overthrow a government or occupation force

中文释义：地下组织；秘密团体

The underground distributed leaflets calling for resistance against the regime.

地下组织散发传单，号召抵抗政权。

Members of the underground met in secret locations to plan their activities.

地下组织的成员在秘密地点会面，策划他们的活动。