That seems to be BE. I would say she can make it there by three, which I think is pretty typical AE.
We also use 'make it'.
We might say she can be there by three, but I am not so sure of at three.
They're different to me- one sets a limit, the other just gives a possible arrival time.
after modal verbs u must use infinitive without to....(gosh very soon i'll be a gold queen:DDDDD)
Modal verbs are usually followed by short infinitives
e.g.He can be of help whenever you want.
i think its be
yeah me too it`s be
She can be there is only correct