What subordinating conjunction can I change Until with in order to make the sentence grammatically correct have friends Prague and Budapest would go Eastern Europe next.?

The sentence is grammatically incorrect because it lacks a subject and verb for the dependent clause. Here's how to fix it:

Original: Until have friends Prague and Budapest would go Eastern Europe next.

Corrected: Because I have friends in Prague and Budapest, I would go to Eastern Europe next.

Here's the breakdown:

* "Until" doesn't make sense in this context. It implies a time period or condition, which isn't present.

* "Because" is a subordinating conjunction that introduces a reason or cause. It makes sense here to explain why the speaker would go to Eastern Europe.

* "I" is the subject of the main clause, and "would go" is the verb.

* "To" is necessary before "Eastern Europe" to indicate direction.

Here are some other options for the subordinating conjunction:

* Since I have friends in Prague and Budapest, I would go to Eastern Europe next.

* As I have friends in Prague and Budapest, I would go to Eastern Europe next.