People with little to no experience with a foreign language often assume that the process of translating is just replacing word A (source language) with word B (target language). This is how the most primitive machine translations functioned, subsequently butchering even the simplest of sentences:

Original

I am studying Spanish before I travel to Mexico.

Translation:

Soy estudiando Español antes de Viajo hasta México.

So after thoroughly confusing anyone you’re attempting to communicate with, one begins to realize that there are a LOT of factors that can complicate a translation. Things like verb tenses, phrasal verbs, slang and regionalisms will all throw the simple “find and replace” method out of whack.

The worst part about these mistakes is that they can happen to even seasoned translators after too much work.  So just remember that it’s never as easy as it seems!