If you want people to reply to an invitation, put (RSVP) at the bottom.

如果想让人回复邀请函，就要在邀请函底下注明尽快回复字样(RSVP)。

youdao

I sent them an invitation, but they didn't even bother to reply.

我给他们寄了个请帖，但他们竟连话也懒得回。

youdao

I sent them an invitation, but they didn't even bother to reply.

我给他们寄了个请帖，但他们竟连话也懒得回。

youdao