I am trying to determine the tense of a certain verb group. This group uses a modal/auxiliary with "be" and the past tense of the action verb. Examples:
- He may be finished.
- She must be loved.
- It can be done.
These can be modified by adding an adverbial preposition.
I can't find help on any tutorial websites, so far.
P.S.: I'm trying to determine if this is something like "present perfect" or "past continuous", etc.
It is not customary to refer to English constructions introduced by modals as tenses (apart from the modal will, which a lot of people bizarrely insist on calling the "future tense") so the simple answer to your question is, none.
Your 2 and 3 are just passives; so on one reading is your 1; but for me a more natural reading is as be followed by an adjective finished (which is derived from a participle).
These are all present tense relating to a state represented by a perfective passive participle (acting as an adjective in a predicative construction). So the aspect is perfect and the tense is present, and there is some conditioning involved in each case which is not that different from the would case (below).
He may be finished.
She must be loved.
It can be done.
The following are indeed (expanding on Colin) often called conditional, future, and periphrastic future, but really there is no particular reason to single out these complex constructions and call them a tense, except that we are trying to impose ideas from Latin on English.
It would be done...
It will be done...
It is going to be done...
In fact these "tenses" come from different metaphors (act of the will that has been frustrated in the would case; moving along the path to achieving the goal).
