居然用英文表达为：actually；

actually：

adv.(在口语中用于强调事实)的确，真实地，事实上;(表示想法与事实不一致因而惊奇)居然，竟然;(礼貌地纠正他人)实际上

相关介绍

That's the only reason I'm actually going.

这是我确实要走的唯一理由。

They reported back that no laws had actually been broken.

他们汇报说并没有真正发生违法的事。

Actually, I'll be a bit late home.

说真的，我回家会晚一点。

I didn't want to say anything without actually reading the letter first.

在未确实读信之前我什么也不想说。

I never dreamt I'd actually get the job.

我做梦也没想到会真的得到这份工作。

The food was not actually all that expensive.

食品居然并不那么昂贵。

Leaving the expense aside, do we actually need a second car?

且不说费用多少，我们真的还需要一辆汽车吗？

Her version of events is subtly different from what actually happened.

她对事件的描述跟实际发生的情况有些微妙的出入。