These two words are in no way interchangeable. “To lie” is an intransitive verb (in other words, it doesn’t take an object) meaning “to recline”. “To lay” is a transitive verb (it needs a direct object) meaning “to place”.
Lie: I will lie down. (no direct object)
Lay: I will lay the book on the table. (the direct object = the book)
The mnemonic device to help distinguish the two goes like this:
To lIe is to reclIne. (Both have a long “i” sound.)
To lAy is to plAce. (Both have the long “a” sound.)
The lie/lay confusion mainly stems from the fact that “lay” serves as the past tense of “lie”. It doesn’t help when popular culture mixes them up, either:
If I lay here
If I just lay here
Would you lie with me
And just forget the world?
–Snow Patrol, “Chasing Cars”
Thanks a lot, Snow Patrol.
Here are the forms of each verb:
lie, lay, lain; lying
lay, laid, laid; laying
Here’s what they look like in the wild:
LIE: The gorillas prefer to lie on banana leaves.
Yesterday, I just lay around the house.
The dog has lain there for two whole days. I hope he’s okay.
How long has this suitcase full of money been lying in the driveway?
LAY: The gorillas like to lay banana leaves on the grass to make a bed.
Yesterday, I laid the book on the counter, but it’s not there now.
She’s laid her new cocktail dress on her bed.
Are you still laying out the napkins for the guests? What’s taking you so long?
So, now, can you find the mistake in the Snow Patrol lyrics?
>>>29APRIL2012 UPDATE: Thanks to the sharp eye of commenter Clarice, Snow Patrol’s reputation as wordsmiths has been salvaged. The “lay” in the if-clause above is perfectly acceptable as it is indeed the past of “lie”–the necessary form for present unreal conditional. My apologies to Gary Lightbody and the gang.<<<
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