Past tense of “to lie” versus past tense of “to lay”
Solution 1:
Mnemonic: “Use a d when there is a direct object”
The paradigm is the fixed-format part which you say you are perfectly clear on already:
| present tense | past tense | past participle |
|---|---|---|
| lie | lay | lain |
| lay | laid | laid |
You say you know that and that you are not asking about that. Fine: that solves the paradigm question, since you already know it.
As for actually remembering which is which, which I presume to be your real question, you need an aide-mémoire. Now, it is easier to construct a mnemonic for past participles than for simple pasts, but this will suffice because it leads to the right answer for both:
- Use the n in recline to match up with the same letter in lain.
- Use the d in direct object to match up with the same letter in laid.
NB: This one also works for the past tense.
Therefore, the key concept for the memory-aid is that direct object begins with the letter d, and so too do the past and past participle of to lay both end with that same letter.
Here’s your distilled memory-aid:
-
If there is a direct object, use a d in the past and past participle — so lay, laid, laid.
-
If there is no direct object, don’t use a d in the past or past participle — so lie, lay, lain.
To distill it even further, your mnemonic for remembering the paradigm is therefore “d for direct object”.
As far as what is meant is concerned, no matter which verb is called (or shanghaied) into service, the transitive use with a direct object always means to place something down while the intransitive one without an object always means to rest, recline, remain.
In other words, while you can lay things, things themselves simply lie there and do nothing.
To illustrate with a more Latinate example of combined forms used as participial adjectives that you might better connect with, underlying means subjacent (so resting beneath) while overlaid means superimposed (so placed on top of something else).