2--Much to my regret, I'll have to meet my girlfriend at the airport then.
 
1--We'd like to invite you for our dress party tomorrow evening, are you free?
 
2--Much as we'd like to, but we've booked up already for that time.
 
1--What a pity! You can't join us.
 
2--So sorry. Next time we'll go, thanks anyway.
 
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注解：
 
1.picnic野餐   
2.booked up日程排满的   
3.pity可惜  

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译文：

1--明天你能参加我们的野餐活动吗？
2--太遗憾了，明天我要去机场接我的女友。
1--我们想邀你们参加明晚的化装舞会，有空吗？
2--我们很想去，但是明晚已有安排了。
1--你们不能参加，真可惜。
2--实在抱歉，下次一定参加，不管怎样还是要谢谢你。