What are the common mistakes...
The very common mistakes are around the right choice of words in translation, syntax, genders, and use of punctuations. Other common errors are in the formation of plurals, and direct & indirect sentences. The cases of the sentences are often misunderstood and thus translated wrongly.
The biggest complication in the Italian language is its gendered nouns. Adjectives come after nouns, unlike English. The use of double-negatives is very common in Italian, here is where the translators stumble. So because of this, you may translate a sentence in Italian to English as “ I don’t know nothing”. In English this will mean …. He/She knows something. But in Italian the sentence meant…. He/She knows nothing.
English has a minimum of 12 tenses, whereas Italian has a maximum of 5 tenses. When a sentence is in a tense for which there is no corresponding tense in Italian auxiliary words are used to convey the same meaning and this is very complicated and tricky. This is where the translations often go wrong.
There are many more. We can discuss that on a separate page. We discussed these few to give you a better understanding of how important it is to choose the right translation partner.