Both of these words refer to the action of putting something down on a surface, or an object/person/animal resting on a surface.
However, lay has a direct object and lie does not.
A direct object is the thing that “receives” the action of the verb.
So when you put your body horizontally on the bed or sofa, you lie down.
When you put a book on the table, you lay the book down. (“book” is the direct object)
You can say that this cat is lying on the piano:
But if you are putting various photos onto a table, you would be laying the photos on the table (“photos” is the direct object)
Now here’s the confusing part: The past tense of lie is lay!
Here are two sentences in the past:
- With LIE in the past:
Last night I wasn’t feeling well, so I lay down for an hour.
- With LAY in the past:
I laid the book down when the phone rang.
Even native English speakers mix these up; some people say “I’m not feeling well – I need to lay down” when the correct phrase would be “I’m not feeling well – I need to lie down.”
Two forms of the verb LIE
The other confusing part is that the verb LIE has two forms/meanings:
- Lie – put something on a surface
Ex) The cat is lying on the piano.
- Lie – say something false, say something that is not true
Ex) He said he got a good grade, but he’s lying. He actually failed the test.
These two forms of the verb LIE have different forms in the past and past participle:
(something on surface)
that isn’t true)
So in the past, we would say:
- The cat lay on the piano for three hours last night.
- David lied about his final test grade last semester.