[General] "Someone else" can take plural forms?

[cubezero3]

The question arose, when I read the following two sentences.

If you flirt, you behave in a way that makes someone else know that you are interested in them.

https://www.usingenglish.com/forum/ask-teacher/128724-make-play.html

In other words, if it's taken, someone has already laid claim to it even if they're not using it at that moment.

https://www.usingenglish.com/forum/ask-teacher/128736-taken.html

My understanding is that them is used in the first sentence because the sex of the person in question, i.e., someone else, is not given. The writer of the sentence could have said him or her in stead. He chose to use them to make the sentence simpler. The addition of the word else after someone and something doesn't lead to a plural meaning.

 

[Nightmare85]

***Neither a teacher nor a native speaker.***

Yes, you're right.
Instead of using his/her, him/her, people simply use their, them.
(In such cases of course.)

Cheers!

 

[Tdol]

I agree- it's not controlled by the use of else:
Someone's left their bag behind.

(There are other ways of doing this and some will recommend trying to rewrite to avoid using the form where possible.)

 

[cubezero3]

I agree- it's not controlled by the use of else:
Someone's left their bag behind.

(There are other ways of doing this and some will recommend trying to rewrite to avoid using the form where possible.)

I suppose in this case I can get away with saying their bag, instead of their bags.

I want to know other ways of expressing the same meaning. However, I don't have a clue where I can find something about it. Could you please do me a favour and tell me, at least, what key words I should use to google.

Thanks a lot.