The protagonist is from a certain country, and in some point of the story he moves to another one that speaks another language. The protagonist learns their language and talks with them in it.
Movies (usually North American ones) set in another country, almost always have one or some characters who speak English, lowering the impact that the foreign language causes. However, the fiction I'm writing is quite long, and I think that only 2 or 3 characters who speak the protagonist's language throughout the whole story is quite inadequate.
Some parts of these movies have dialogs in the local language, but with subtitles. What about a written story? Provide the translation right after? That would be partially good only if these parts are few if compared to the whole story's dialogs, but that's not my case.
Also, fictions set in another country, but that don't have a change in the local language, are much easier than those that do have, because if, for example, the story is an adaptation from a Chinese story, anyone would know that though every character is speaking English, they would actually be speaking in the local language.
But would this be possibly applicable to the situation when there's a country switch? All dialogs in the other country will be in the same language as the ones in the initial country? Wouldn't it be weird or unrealistic?
Sorry, I think I didn't explained much clearly. I explain:
The problem is the language in the dialogs, not the narration. This story involves a lot of dialogs, and the protagonist moves to another country and learns their language. The problem with this moving is the change in the language in the dialogs, that, in reality, would be another one. And my question is how to deal with this situation in the story.