I have so many friends, but deep down, underneath, I have a fear of loneliness.

我有这么多朋友，但是内心深处我还是有一种对孤独的恐惧。

《柯林斯英汉双解大词典》

He seems confident but deep down he's quite insecure.

他好像很有信心，实际上却没什么把握。

《牛津词典》

She can seem stern, but deep down she's a very kind person.

她看上去可能严厉，其实心地非常善良。

《牛津词典》

Alfred tried to sound big, but deep down he was like a child.

VOA: special.2010.09.11

So I haven't done magic, I've given you a really fast way to solve a knapsack problem, but it's still exponential deep down in its heart, in something.

所以我并没有施魔法，我已经告诉了你,一种快速解决背包问题的方法了,但是某些方面它的核心仍然是指数增长的。

麻省理工公开课 - 计算机科学及编程导论课程节选

These are very deep lesions that go not just on the surface of your skin like a blister would, but down into the dermis or deeper layers of the skins, as well.

这些伤非常深,它们不仅像水泡那样存在于皮肤表面,还深入到真皮层或者皮下更深的地方

耶鲁公开课 - 生物医学工程探索课程节选

"With all footballers, you have a point to prove to people, but deep down it's proving the point to yourself, " said Lennon.

BBC: Celtic continue striker search despite Samaras form

That was our compromise, but deep down I was certain that victory would be mine once he experienced how incredible my purchase was.

FORBES: Learn to Trust People with Firsthand Experience

"Everyone's entitled to their opinion, but deep down, if there was an opportunity for a life-changing contract, he's shaving his damn beard, " Wells said.

WSJ: Yankees: No Beards��And That's Final