The Democrats met just three blocks from the White House, but with half a meter of snow on the ground from a winter storm, the trip became dangerous.

VOA: standard.2010.02.06

It's dangerous to want to get away from earth awhile, to get your feet entirely off the ground.

想要逃离地面一会，让自己的双脚同时离开地面很危险。

耶鲁公开课 - 现代诗歌课程节选

"The situation currently on the ground is quite dangerous,".

VOA: standard.2009.04.09