He needn't have come so early; nobody is here yet.
Could he have spoken to her this morning?
They may be working outside in the garden.
She would go to the film if she had time.
She can't be ill; she was fine when I spoke to her five minutes ago.
You shouldn't have yelled at your parents.
I have not been able to find the time to write.
The pupils in this school have to wear a uniform.
There is a possibility that the plane might have already left.
I'm sure the cake must have been eaten.
Hope this helps! Don't take my word for it!!