你今晚想参加我们的晚宴吗？
Would you like to join us for dinner tonight?

For example:
A: Would you like to join us for dinner tonight?
你今晚想参加我们的晚宴吗？
B: Great. I'd be glad to.太好了，我乐意参加。

恐怕我不得不推辞这个邀请。
I'm afraid I have to decline the invitation.

For example:
A: I'm afraid I have to decline the invitation.
恐怕我不得不推辞这个邀请。
B: Maybe some other time?另外换一个时间，可以吗？
decline(v.)拒绝

我要看一下我的行程表。
I will check my schedule.

For example:
A: Will you and your associates be able to attend?
您和您的同事们能出席吗？
B: Will I check my schedule.我要看一下我的行程表。

那天晚上该穿什么？
What is the attire for the evening?

For example:
A: What is the attire for the evening?那天晚上该穿什么？
B: Semi-formal and do bring your spouses.
半正式，并请带着各位的夫人或先生。
attire(n.)服装

这回我不能参加。
I will pass this time.

For example:
A: I will pass this time.这回我不能参加。
B: I am sorry, but maybe some other time.对不起，下回另找时间吧。

你们今天肯赏光前来赴宴，我感到非常高兴。
I'm really very glad you were able to come.

For example:
A: I'm really very glad you were able to come.
你们今天肯赏光前来赴宴，我感到非常高兴。
B: It is very kind of you to invite us to a dinner in such a
wonderful restaurant.
你们在这么好的饭店设宴招待我们，真是太感谢了。

我要借花献佛。
I'll propose a toast provided by the band.

For example:
A: I'll propose a toast provided by the band.我要借花献佛。
B: And let's drink again for future closer cooperation. Prosit.
为了我们今后更加紧密的合作，再干一杯！

今晚咱们出去吃吧。
Let's dine out this evening.

For example:
A: Let's dine out this evening.
B: Let's dine out this evening.今晓咱们出去吃吧。
Sounds great.主意不错。

托马斯先生，欢迎光临，请入席。
Welcome, Mr. Thomas. Please sit down.

For example:
A: Welcome, Mr. Thomas. Please sit down.
托马斯先生，欢迎光临，请入席。
B: Thank you.谢谢。

昨天因为忙,没能去机场接你们，请原谅。
I'm so sorry that I was not able to meet you at the airport yesterday, as I was rather busy.

For example:
A: I'm so sorry that I was not able to meet you at the airport yesterday, as I was rather busy.
昨天因为忙,没能去机场接你们,请原谅。
B: Not at all.没关系。

来，我提议为我们客人的健康，干了这杯。
Here! Let me propose a toast to our guests' health.

请随意。
Please help yourself.

For example:
A: Please help yourself.请随意。
B: Thank you. Very delicious.谢谢。真好吃。
help oneself 请随便

请随意，爱怎么吃就怎么吃。
Make yourself at home and eat the way you like best.

For example:
A: Make yourself at home and eat the way you like best.
请随意，爱怎么吃就怎么吃。
B: I would like to try your chopsticks.我就试试用你们的筷子吧。

您能光临我们宴会，我不胜荣幸。
It's my honor to have you to attend our banquet.

For example:
A: It's my honor to have you to attend our banquet.
您能光临我们宴会，我不胜荣幸。
B: Thank you for your invitation.谢谢您的邀请。

宴席已准备好了，请入座。
Banquet is ready. Please be seated.

For example:
A: Banquet is ready. Please be seated.宴席已准备好了，请入座。
B: All right. Thank you very much.好的。非常感谢。

下一次，该是各位到我家来做客了。
Next, you'll have to come to my house for dinner.

For example:
A: Next，you'll have to come to my house for dinner.
下一次，该是各位到我家来做客了。
B: It's a great honor. I accept the invitation.
太荣幸了。我接受这个邀请。

这个宴会是临时决定的。
The party is causal.

For example:
A: The party is causal.这个宴会是临时决定的。
B: What a surprise, but I certainly will go to the party.
好意外，不过我当然接受这个邀请。

这是我们经常聚会的地方。
This is the place we sometimes get together.

凡是有重要人员来访，我们在这里举办招待会。
We have a reception here when someone really important.

你要先喝点儿什么酒呢？
What would you like to drink first?
What would you like to have for a drink first?

你要点全套大餐吗？
Would you like to order a full-course meal?

甜点你要吃什么呢？
What will you have for dessert?