in fact or really

I didn't actually see her - I just heard her voice. 实际上我并没有看见她，只是听到了她的声音。

So what actually happened? 那么到底发生了什么事呢？

used in sentences in which there is information that is in some way surprising or the opposite of what most people would expect

I didn't like him at first, but in the end I actually got quite fond of him. 起初我对他并没有好感，可最后我竟然挺喜欢他的。

I'm one of the few people who doesn't actually like champagne. 有个别人还真是不喜欢香槟酒，我就是其中之一。

humorous Don't tell me he actually paid for you! 别跟我说他居然替你付了钱！

used as a way of making a sentence slightly more polite, for example when you are expressing an opposing opinion, correcting what someone else has said, or refusing an offer

"Alexander looks like he'd be good at sports." "Actually, he's not." “亚历山大看上去很擅长运动。”“事实并非如此。”

Actually, Gavin, it was Tuesday of last week, not Wednesday. 实际上呢，加文，那是上星期二，不是星期三。

"Do you mind if I smoke?" "Well, actually, I'd rather you didn't." “我抽支烟你介意吗？”“嗯，说实话，我希望你还是别抽。”