The verbs lie and lay sometimes creates confusion while communicating.
Lie/lay/lain- These are the three tense forms. The verb lie does not take a complement. It means to rest or to be situated in a place. It is often used with the preposition down.
For example:You are tired. Please lie down for sometime.(Present tense)
I went to the beach last Sunday. I lay down to relax for sometime.
My mother is sick. She has lain down.
Please don't get confused the above verb with 'lie' which means not true. For example: He lies very often. Mary has lied to me. The student was punished because he lied to the teacher. Lie is also a noun. It means dishonesty. Example: It is a lie. Don't try to fool me. You are lying.
You can also say : Don' tell a lie.
However, lay means to put somebody or something on a surface.The three forms are lay/laid/laid.They take a complement.
For example:Please lay your books on the shelf.(Present tense)
When the robber was caught by the police , he laid down his pistol.(Past tense)
The infant's mother laid it on the bed very carefully on the bed(Present perfect tense)
The dog always lies under the cot.
Mary lay on the sofa after she came back from work .
The naughty boy has lain his school bag on the dining table.
My mother lays the cups on the cupboard.
Rita laid her comb on the dressing table.
The hen has laid some eggs.