The congress will be pleased to send a formal letter of invitation to any individual requesting one.
大会将很乐意为正式的邀请函，要求任何个人之一。
We'll email you formal letter of invitation later, with more detailed information about this conference.
迟点我会把正式的邀请函和关于这次会议更详细的信息电邮给您。
I'm very sorry to inform you that according to my experience, the official formal letter of invitation only aims at commercial visas, in which no child is allowed to be involved.
根据我的经验，很抱歉，官方正式的邀请函只是针对商务签证，是不允许把小孩子放到邀请函之中的，所以恐怕帮不到你。
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