1
I’m laying on the sofa because I feel tired.
I’m lying on the sofa because I feel tired.
Use lie when you mean ‘be in a flat position’. The -ing form is lying: ‘The dog is lying on the floor.’ In standard English, lay means ‘put something down’, so it is followed by a person or thing: ‘Lay the book on the table.’
2
Yesterday I lied down for an hour after lunch.
Yesterday I lay down for an hour after lunch.
The past form of lie meaning ‘be in a flat position’ is lay: ‘I lay down after lunch.’ Use lied only for lie meaning ‘say something that is not true’: ‘He lied about his age.’
Check our grammar lesson on the difference between lay and lie.
See LAY