Lie / lay / lain (recline) / Lay / laid / laid (put down) / Lie / lied / lied (say something untrue)
Different formsLie meaning recline takes no object and has the forms lie, lay, lain. Lay meaning put something down takes an object and has the forms lay, laid, laid. Lie meaning say something untrue is regular: lie, lied, lied.
Lie / lay / lain (recline)
Use when
The subject rests, reclines or remains in a position without acting on an object.
Example
“The signed copy lay on the desk overnight.”
Lay / laid / laid (put down)
Use when
Someone or something puts an object down; this verb must have an object.
Example
“She laid the signed copy on the desk.”
Lie / lied / lied (say something untrue)
Use when
Someone knowingly says or writes something that is not true.
Example
“The supplier lied about completing the security test.”
Quick check
lied down when lay down is meant, lay about the figures when lied is meant, layed the papers down, has laid on the desk when has lain is meant
Usage note
The overlap is that lay is both the present form of the transitive verb and the past form of lie meaning recline. Lain is mainly used after has, have or had. Write laid, not layed.