Quote Originally Posted by penagate
We may have lost the second person singular form, but never fear, for we have gained a second person plural pronoun, y'all.
One of the problems caused by the disappearance of "thou" in the English language can be found in translation. Once I had to translate the following sentence from Italian into English:

Da allora cominciammo a darci del "tu".

Its literal meaning is, "From that moment on, we started using 'thou' to address each other".

In Italian, when you make friends with someone, you stop using the second person plural (voi) or the third person singular feminine (lei) and start using the second person singular to address him or her. (Please note that the third person singular feminine is used to replace the second person singular.)

Now, I think that a good translation for a sentence like the one above could be, "From that moment on, we started calling each other by (the) first name". Nevertheless, as you proceed with your translation, you may find yourself in trouble if in the text there is an explicit reference to the personal pronoun (e.g. "Why did you say, 'You are right' instead of 'Thou art right'?").

That's why I believe that the loss of the second person singular in English can be an enormous headache if you work as a translator.