To suss this out, I called up some linguists: Gretchen McCulloch, who specializes in analyzing netspeak (her Toast essay explaining “the grammar of Doge” is a gorgeous example), and Ben Zimmer, a linguist with Vocabulary.com who writes for the Wall Street Journal. As they pointed out, this style of wordplay initially appeared—like most online memes — on image-boards, Tumblr and Youtube. An early version was the meme “that feel when”; variants morphed into the standalone phrase “that awkward moment when”, which by last year was common enough to appear as a movie title.

But it’s more than just movie titles. This stylistic gambit— “that moment when …”, “the thing where …”, “when you realize …” — is omnipresent now. And that’s because it achieves a few conversational goals:

1) It creates a little puzzle.

Grammatically speaking, what’s going on here is the rise of the “subordinate clause.” A subordinate clause isn’t a sentence on its own. As the name implies, it requires another sentence fragment to complete it, as with this example that McCulloch and I looked at on Yik Yak:

Usually you can quickly deduce what the missing part would be. Maybe it’s something like You, sadly, always know what to do when she’s holding a dog on her Tinder and you’re like, “cute dog.” Or maybe the full sentence that emerges in your head is more convoluted, like Nothing is more bittersweet than reflecting on the challenges of dating someone who is superficially attractive but owns a pomeranian and thus, you worry, has all sorts of dog/partner priority issues, which you can instantly intuit when you’re using a dating app and see someone when she’s holding a dog on her Tinder and you’re like, “cute dog.”

The point is, it’s up to you imagine the rest of the utterance. It’s like the author is handing you a little puzzle. Subordinate-clause tweets and Yik-Yak postings seduce us into filling out that missing info, McCulloch says. “Our brain has to work a little bit harder to figure out what it’s referring to, and so making that connection is very satisfying. It’s like getting a joke. You have to draw that connection for yourself a little bit — but because you can do it, it works really well.”

A historic parallel? The crazy, long chapter headings in 19th-century novels, which often were also dependent clauses, inviting the reader to imagine the rest of the baroque narrative. “In Which Our Protagonist Meets A Dashing Stranger,” McCulloch jokes. “The ‘in which’ is doing a very similar thing.”

But there’s another reason so many people use the subordinate clause today. It accomplishes an even more subtle goal …

2) It makes your feeling

seem universal.

As McCulloch notes, when someone posts a subordinate clause like this, the missing information, in a way, is you. It’s saying, wow, you can imagine this feeling, can’t you? You’ve had this feeling, haven’t you? “They’re trying to universalize this experience, and make it kind of an Everyman type of experience,” she adds. “It’s saying, ‘this thing has happened to me, this has happened to me before and this was my reaction, it’s probably happened to other people and they’ve also reacted the same way.”

Or as Zimmer puts it: “To be elliptical in that way requires various kinds of shared knowledge — the shared knowledge of situation.”

3) It’s short.

This isn’t actually a point of McCulloch or Zimmer’s; it’s mine. But it occurs to me that one big power of today’s standalone subordinate clause is that it’s punchy. Because it alludes to utterances that stand outside the clause — and the reader fills in the blanks — it compresses a lot into very few words. That works nicely in smartphone environments where space is tight, and brevity is the soul of wit.

But McCulloch’s most fascinating observation about this meme is a big, meta one …

4) It’s a glimpse of the next big way

the Internet is changing language.

For the first fifteen years of the mainstream Internet, the main way language changed was at the level of the individual word. We invented a lot of ‘textisms’ — short forms like ‘ur’ for “you’re”, LOL-style acronyms, or alphanumeric l33tspe@k. And of course, a lot of words got invented, like “selfie”.

What’s happening now is different. Now we’re messing around with syntax — the structure of sentences, the order in which the various parts go and how they relate to one another. This stuff people are doing with the subordinate clause, it’s pretty sophisticated, and oddly deep. We’re not just inventing catchy new words. We’re mucking around with what makes a sentence a sentence.

“Playing with syntax seems to be the broad meta trend behind a whole bunch of stuff that’s going on these days,” McCulloch tells me. And it goes beyond this subordinate-clause trend. Many of the biggest recent language memes were about syntax experimentation, such as the “i’ve lost the ability to can” gambit (which I wrote about a few months ago), or the gnarly elocution of doge, or the “because” meme. (Indeed, Zimmer points out, the American Dialect Society proclaimed “Because” the Word of the Year for 2013, largely because it had been revitalized by this syntax play.)

Why would we be suddenly messing around with syntax? It’s not clear. McCulloch thinks it may be related to a larger trend she’s identified, which she calls “stylized verbal incoherence mirroring emotional incoherence”. Most of these syntax-morphing memes consist of us trying to find clever new ways to express our feelings.

“You want to convey that you’re kind of overwhelmed by your emotions,” she says. “But you don’t want people to think that you’re completely naive about it. So you’re maintaining a certain level of sophistication. You need to stylize your incoherence, so that it’s part of a broader thing people are doing. You don’t just kind of keysmash all over the place. You also want to be witty while you’re doing it.

“You get more attention online if you’re witty, and people actually engage with you if you’re witty about your feelings.”

On the other hand, if you really don’t like this trend, there is—as it happens —an image-meme for your feelings, too. Better yet, it’s a complete sentence!