A wild card 未知数，外卡
The script of this programme 本节目台词
Rob: Hello and welcome to Authentic Real English. I'm Rob and joining me today is Feifei.
Feifei: 大家好！咱们办公室新来的那位同事听起来不错的哈？What about that new guy who's started in the office?
Rob: You mean Brian?
Feifei: Yes, he's very funny – 总给我们讲笑话，昨天他还在办公室给我表演用橙子玩杂耍 - he was very good.
Rob: Hmm, if you say so. He might be funny but I haven't seen him do much work - I think he's a bit of a wild card.
Feifei: A wild card? Brian 是“一张疯卡”？你的意思是他可能是红桃心，方片，黑桃或是梅花？什么呀？我不懂。
Rob: No, no, although the expression does come from playing cards - here, it means he is unpredictable, he's someone we don't know much about so we're not sure how he's going to behave in the future.
Feifei: Oh do you think so? 原来在英语里，我们可以用 a wild card 来描述一个我们不太了解的、行为不可测的、有未知数的人。这个表达现在也常备用在选秀比赛中用来描述“外卡选手”。Now you've said it, yes Rob, Brian is unpredictable!
Rob: OK. Let's hear some more examples of this phrase...
- Jack is too much of a wild card to get a place on our team.
- We're taking a gamble, she's a wild card, but let's hope she delivers what she promises.
- The wild card in this competition is Chelsea: nobody really knows which way the score will go.
Rob: Right, have you got that? A wild card can describe someone who is unpredictable or who behaves in an unexpected way. But although Brian is a wild card, I wish he'd settle down and do some work instead of joking around all the time.
Feifei: 老实说，其实你也想像 Brian 这样生活吧？
Rob: Not at all - but Feifei what kind of card would you call me?
Feifei: Oh Rob, you're my favourite card - you're ACE!
Rob: Ace! Gosh Feifei, you're such a card!
Feifei: See you next time.