Traveling through cold air causes your eyes to tear, making it extremely difficult to see.

穿过冷空气会使你的眼睛，撕裂，使得它极难看到。

youdao

But this can be extremely difficult to see right now as we are smack-dab in the middle of it, directly in the thick and dense processing phase where it is so easy to get lost in fear and anxiety.

但是现在很难看清楚这点，因为我们不偏不倚正好处在它的中间。 在这最黑暗迷茫的时期，很容易迷失在恐惧和焦虑里。

youdao

Triggering a tiny earthquake is easy (see above about oil production), but triggering an earthquake big enough to matter would be extremely difficult.

引发小地震是很容易的(参见上述有关石油开采的内容)，但是引发大地震是极其困难的。

youdao

"If many of these companies hide behind commercial confidentiality it is extremely difficult... to see whether there is probity and value in our money that is being spent, " she told the Today programme.

BBC: Does government outsource too much?