I am writing a tech blog. In this blog, I am using an analogy to explain something. And the analogy has this story that begins in Spain. And there's a sentence I used to convey a part of that analogy but now I am not sure if that sentence is grammatically correct or not.
So what I actually want to convey to the readers of this blog is that I received a letter, I opened it but the language in which the letter was written was Spanish.
And to convey that I wrote, When I opened the letter, it was written in Spanish...
. I don't know why but it seems like it is incomplete. Is this sentence grammatically correct?