2--The invitation came in the mail yesterday.

1--I was worried it got lost in the mail.

2--Unfortunately, I can't go to your party. I wish I could.

1--I'm sorry to hear that.

2--My mother-in-law is visiting that day.

1--I'm really sorry that you can't come.

2--If I could sneak out of the house, I would, but my wife would kill me.

1--I wouldn't want that on my hands.

2--The next party you have, I promise I will be there.

1--What if your mother-in-law visits again?

2--Thankfully, she only comes once a year.

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注解：
 
1.invitation邀请
2.Unfortunately不幸地
3.mother-in-law岳母 

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译文：

1--你收到来我聚会的邀请了吗?

2--邀请函昨天到的邮箱。

1--我担心它在邮寄过程中丢失了。

2--很遗憾，我不能参加你的聚会。我希望我可以去。

1--很遗憾听到这个消息。

2--我的岳母那天来。

1--真的很遗憾那天你不能来。

2--如果我能溜出家里，我会来的，但我的老婆会杀了我。

1--我不想看到发生这样的事。

2--你的下一个派对,我保证会去参加。

1--如果你岳母再次拜访呢?

2--值得庆幸的是,她一年只来一次。