I see a lot of people using they/them pronoun on their twitter handles. And when I googled about it, I have come to know that it is a Gender-neutral pronouns.
However, isn't it wrong to use words like 'they' and 'them' for a single person?
For example, when talking about such person, one has to say,
They are walking down the road.
which makes it plural. However, for a male/female pronoun, one can say,
He/She is walking down the road.
First, the singular they has been in use since before English became modern English; it was used in Middle English in the 14th century. It only became déclassé around 1900 when some overly stuffy grammarians started acting up.
Second, its use as a gender neutral singular is a bit more complex: It can be used either when we don't know the gender of the person:
Someone's coming up the street! They are coming to our house!
or when the person is nonbinary and prefers "they". Nonbinary people vary in which pronoun they prefer. Some use he or she, some use e, some use they; there are other possibilities to. Many prefer to use their names whenever possible, and eschew pronouns as much as possible. For instance, if the person's name is (say) Basil (as one nonbinary person I know is named):
Basil is coming up the street! Basil is coming to our house! Now Basil is knocking on our door!
The "singular they" prevents the awkwardness of using "he/she" or guessing the gender wrong. For example, I might be talking about you in a chat room, and say:
Did you see the latest question posted by Dawny33? She's been asking some interesting questions.
However, if you happen to be male, that might create an awkward moment. So, I might say instead,
Did you see the latest question posted by Dawny33? They've been asking some interesting questions.
(There are other ways to circumvent this issue, too, but this one is often used.)
"Singular they" does have a long history in English, and cannot be considered wrong. It has been more favored in recent decades to avoid "default he", that is, the use of male pronouns for a person of unknown or unspecified gender. That has a much longer history in English than "Singular they" does, but is now considered to show gender bias and is strongly frowned on by many people. It does avoid writing "s/he" or "he/she" or "he or she". On the other hand, it loses the information about singular vs plural.
Personally, I strongly dislike singular they and will not write it under any circumstances whatsoever. I will usually use "s/he" or "he or she", which I do not find at all awkward. I do not know any people who have expressed specific pronoun preferences to me – I am not sure how I would handle the case if I had occasion to write of a person who preferred to use "they". I might add that if personal preferences are allowed in such matters, that I prefer not to be referred to as "they", except as part of a group.
At one time I hoped for consensus to form on a new, coined pronoun for a singular person of unspecified case. I favored "zie" with objective case "zir" and possessive "zis". But no wide consensus on this has developed, and I do not now expect one in my lifetime.
Singular they has solved many problems especially the gender bias.The history of single they has well been explained in the previous posts.
Gender bias :Indefinite pronouns like nobody, somebody used to be treated as masculine gender. so it was considered gender bias.So the use of singular they solved the problem of awkward construction such as he/ she.
Now we can say:
Everybody should bring their Hall tickets instead of his/ or his/ her hall ticket.
When the gender of a person is not known
Sometimes the gender of a person is not known such as on sites like this.Then singular they come to our rescue.
We say:
They are a new comer to this site
Correctness: When the native speakers start using singular they in all the occassions, it should be considered idiomatic and grammatical.Grammar books can only describe language, they can not prescribe rules.
Here is a link which shows the usage of singular they.
