Lie means “to recline or rest on a surface”; lay means “to put or place something.”
Lie is an intransitive verb: It does not take a direct object.
Lay is transitive: It takes a direct object.
Here are the standard English forms of these verbs.
BASE FORM |
PAST TENSE |
PAST PARTICIPLE |
PRESENT PARTICIPLE |
lie |
lay |
lain |
lying |
lay |
laid |
laid |
laying |
The past-tense form of lie (“to recline”) is lay.
The past-participle form of lie (“to recline”) is lain. If the correct English seems too stilted, recast the sentence:
The past-tense form of lay (“to place”) is laid.
The present participle of lie (“to rest on a surface”) is lying.
Exercises:
Irregular verbs 1
Irregular verbs 2
Irregular verbs 3