Breakdown of Если вы покажете оригинал, который вы нашли, то я прочитаю текст.
я
I
вы
you (plural)
текст
text
прочитать
to read (perfective)
Questions & Answers about Если вы покажете оригинал, который вы нашли, то я прочитаю текст.
Why does который look like it is in the Nominative case here, even though it is the direct object?
In the clause который вы нашли (which you found), the word который is the direct object, so it must be in the Accusative case. It takes its gender from the word it refers back to, оригинал, which is masculine. Because it represents an inanimate object, its masculine Accusative form is identical to the Nominative form: который.
Why is покажете (will show) in the future tense, while the English translation says "If you show"?
English often uses the present tense for future conditions (like "If you show me later..."). Russian is more literal: since the showing will happen in the future, you must use the future tense покажете after если.
Do I always have to use то when I use если?
No, but it is very common! The combination Если ..., то ... translates directly to "If ..., then ...". Adding то (then) gives the sentence a nice rhythm and clearly introduces the consequence of the condition.
Why use the perfective verbs покажете and прочитаю in this sentence?
Because the sentence is talking about one-time, completed actions with a clear result. You will show the original once, and I will read the text to completion. If we used imperfective verbs here, it would sound like a recurring habit or an ongoing, unfinished process.