Modals and adverbs
Adverbs are often used with modals to add to their meaning:
Surely
you can't have said that to her!
I might
just
tell you all about it.
I could
easily
have been hurt.
You
really
shouldn't have gone to so much trouble.
I will
definitely
call you tomorrow.
You can't
possibly
be serious.
She
obviously
must have forgotten it.
He could
probably
help us a lot.
I can't
exactly
remember when I first met her.
You should
absolutely
take up that course.