Hello everybody! :-)

Mark J. Reed's prediction seems logical, yet simple enough to be adopted:
> I am loath to predict the future, but I imagine that despite these efforts
> we are more likely to end up with singular "they" being accepted in more
> and more contexts that "sound weird" today until it is simply the English
> third-person pronoun - undifferentiated in number just as our second-person
> pronoun is.

If I am informed correctly, the career of "you" has begun in the plural. So,
I can fully understand that it requires a verb in the plural till the present
day - even for its relatively new role in the singular and after "thou" had
fallen out of use.

Now, if the community of English speakers tries to apply the evolution of
"you" to the case of "they", there will be some inevitable ambiguity as has
been pointed out already in this thread. I propose a radical solution which,
of course, could and probably will be painfully unenglish to a native speaker
(which I am not).

My suggestion is to finish the evolution of "you" by separating the unchanging
pronoun form ("you" in the singular and plural) from the, currently, also
unchanging plural of the verb. That is: "you is" would be the new singular
version and "you are" would remain the plural. This would eventually pave the
way for "they" to essentially become the same but in the third person.

Mark J. Reed's example would then read: "Pat's roommate is coming. They has
their own shoes."

The very same approach wouldn't work too well in German (my mother tounge)
because, there, the third-person plural pronoun ("sie") also functions as the
female third-person singular pronoun - which may lead to some confusion.

Just my two cents. I wish you all a wonderful weekend,