Use lay when you put something down; it needs an object. Use lie when a person or thing reclines or rests; it does not take an object. The confusing part is that lay is also the past tense of lie.
Compare the meanings and forms
| Meaning | Present | Past | Past participle | Example |
|---|---|---|---|---|
| Put something down | lay | laid | laid | I lay the book on the desk. |
| Recline or rest | lie | lay | lain | I lie on the sofa after work. |
The past forms are different because these are two separate verbs. For the “put something down” verb, the forms are lay–laid–laid. For the “recline” verb, they are lie–lay–lain.
Check whether there is an object
An object is the person or thing that receives the action. If you can ask “lay what?” and name something, lay is the verb you need:
- Please lay the papers on my desk. (Lay what? The papers.)
- She laid her coat across the chair.
If the subject simply reclines or rests, use lie in the present:
- I need to lie down for a few minutes.
- The cat lies in that sunny spot every afternoon.
A useful contrast is: “I lay the baby in the cot” means I put the baby there; “The baby lies in the cot” describes the baby’s position.
Why “I lay down yesterday” is correct
In the past, lie (recline) becomes lay. So I lay down yesterday is correct: there is no object, and the sentence describes where I rested. By contrast, I laid down the bags yesterday uses lay (put something down) in the past and has an object: the bags.
For perfect tenses, use lain for reclining and laid for putting something down:
- She has lain there for an hour.
- She has laid the towels on the bed.
The -ing forms are lying (reclining) and laying (putting something down): “He is lying on the grass”; “He is laying a blanket on the grass.”
One more meaning: lie can also mean “say something untrue.” Its past forms are lied and lied: “He lied about his age.” This is a different verb from lie–lay–lain.
Quick check
Check your understanding
At bedtime, I the baby in the cot (lay or lie; meaning: put the baby there).
After the long walk, we under a tree for a while (lay or laid; meaning: reclined yesterday).
The parcel has been beside the front door (laid or lain; meaning: someone put it there).
The dog is by the gate, resting in the sun (lying or laying; meaning: reclining).
Answers and explanations
lay
Use lay when putting someone or something down; “the baby” is the object.
lay
Lay is the past tense of lie when it means recline; there is no object.
laid
Laid is the past participle of lay, meaning put something down.
lying
Use lying for the -ing form of lie, meaning recline.
