I swear that I am not usually THAT guy . . . the one who plays grammar fiend on social media. I really don't, but when I saw the following (or something close because I can't find it again), I had to dip my oar in.
Isn't it wonderful to lay in the sun and read all day long?
I swear that I would have let it go on most occasions, but it was posted by a library, and to whom much is given much is required.
So I replied:
Dear Library. It's lie.
Please don't think less of me. I was gentle.
I don't hunt social media judgmentally because, truthfully, I am not even close to being an expert, but on rare occasions, like this one, I feel obligated to be THAT guy.
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I intended to stop with the above, but, as a public service, I will try to explain the difference between the verbs to lie and to lay, just in case you were daydreaming during that lesson in school.
Think of to lie as an action taken by a subject. I (the subject) lie down, at least in the present tense. I would be correct to say, "I am tired and I'm going to lie down," because I am taking the action.
It would not be correct to say, "I am going to lay down."
If we put a book on the table, we lay the book on the table because the book is an object receiving the action. We don't lie the book on the table; we lay it on the table. But from the book's point of view, it is lying on the table, not laying on the table. I am lying down; I am not laying down.
It's pretty simple really, but there are two tricky bits which are what gets us all befuddled and confused and causes us to throw our hands up in despair over this crazy language of ours.
(1) We can lay ourselves down as long as we are treating ourselves as objects, as in the book example above. "I [subject] am so tired that I must lay my body [object] down." Got it, or is your head hurting?
(2) Even stranger and more confusing: if we are describing the action of lying down in the past, then in that case we lay down. You see, lay is also the preferred past tense usage of the verb to lie. It just seems better to our ears to say lay in that instance rather than did lie or lied which, although technically correct, feel wrong. Most of us use lay instead of did lie in that case because it seems better to our ears for some reason,
So . . . we use to lie as an action that a subject does, but we use to lay when an action done to an object.
Usually, by the time people get to the exceptions, they then get confused all over again about the basic usage of to lie versus to lay, but I am sure that it is crystal clear to you now. Right?
Now, stop telling your dog to lay down; tell Rover to lie down. Alternatively, you can tell Rover to lay yourself down.
Here is Grammarly's take, but I wrote mine first, or at least I wrote mine before I read hers. https://www.grammarly.com/blog/lay-lie/ .