"I wish you were here." is grammatically correct in English. And yes it is the "subjunctive mood". Its meaning is closer to "I wish for you to be here" than "I wish you had been here".

This random page I found on the internet has a pretty decent explanation of the subjunctive:

https://www.learngrammar.net/a/examples-of-the-subjunctive-m...

"I wish you were _there_", not "I wish you were here"

> I thought it was “led”

It is "led". I notice the web using "lead" for both the present and past forms a lot--presumably because it sneaks past spelling checkers and autocorrect. (There's also a correspondence to "read" (long e) where "read" (short e) is also the past tense. Yeah, welcome to English.)

And, I'm almost sorry for pointing it out if you haven't noticed it. Once you do notice it, you see it everywhere and it's a big, jarring speedbump when you read.

"I wish you were here" -- in this location, now or in the past.

"I wish you were there" -- at another location, now or in the past.

"I wish you had been there" -- at another location, in the past.

"had been" means that the action is concluded. "were" is for both continuing and concluded actions, and more words are necessary to glark it from context.

"Were" is the subjunctive. I think it comes to English from the German subjunctive form "wäre". It's not the same word as "were", as in "We were running".

The example you've chosen refers to an event in the past, so "were" seems to be ambiguous in that context, because it could be "you were there", prefixed by I wish - i.e. the writer isn't trying to use the subjunctive at all, which I think is nowadays OK.

"I wish you were here" is a clearer example. That is clearly present subjunctive. "I wish you had been here" would be referring to an event in the past - so that's some kind of past subjunctive.

I regret the death of the subjunctive.

Present: "He leads me to believe in grammatical rigor."

Past: "She led me to that conclusion long ago."

Past, growing popular but historically incorrect: "She lead me to that conclusion long ago."

Noun: "I licked the sweet lead off the wall."

Also noun: "After six rounds of chess-boxing-sprinting, it was not clear to either of the participants who had the lead."

Also also popular but historically incorrect noun: "We have eighty thousand lead-free ornaments on this wall, each lit by an individually-addressable led."

And each led connected to power by its own lead. Incidentally, are those ornaments electrically-powered? Don't they need leads to provide power?

This is spelling, not grammar. It's the same word, not a noun, spelled differently.