@starlighter,
Quote:For example: "All she does is sleep every day!"
1.What is the name of the grammar structure?
2. Why do we omit 'to' before the verb?
3.Why can't we use a noun or gerund after 'do'? Many thanks.
2. Because it is not an infinitive --> She sleeps every day.
3. Because the present simple describes an habitual or a routine event.
I eat oatmeal every morning. I go to bed at 10.