Some of the most often confused words are lie and lay in their various forms. Let’s look at them a little closer.
The verb lie can have two totally different meanings, either to tell a falsehood or to recline. In the present tense both words are identical and their meaning can usually be distinguished by the context they are used in.
Example: Peter lies to you when he says that he lies in bed for only two hours every night.
However, they differ in the past tense and past participle.
Example: Peter lied to you when he said that he lay in bed for only two hours last night.
Even more confusion exists about the use of the verbs lie (as in recline) and lay (as in put or place something). It is important to understand that lay is a transitive verb, that means it requires a direct object, something that is being placed. Lie is intransitive and therefore has no direct object.
Example: Patty laid the book on the nightstand and then lay down on her bed.
The following table shows the different forms for these three verbs:
| Meaning | Present | Past | Past Participle | Transitive |
| to tell a falsehood | lie, lying | lied | has/have/had lied | No |
| to recline | lie, lying | lay | has/have/had lain | No |
| to put or place | lay, laying | laid | has/have/had laid something | Yes |
Source: www.grammarbook.com
As a general rule, laid is not to be used with people, but, as a retired English teacher said with a smile on her face, the exception is when it involves two people.