(Shall or will, unchanged, with the perfect infinitive, have been.*)

1. (If) I shall have been(If) we shall have been
2. (If) thou shall have been(If) you shall have been
3. (If) he shall have been(If) they shall have been

POTENTIAL MODE[*]

[Footnote *: The distinct potential mode is no longer used by many authorities on grammar, and the potential forms are regarded as of the indicative mode. It has, however, been thought best to use it in these model conjugations.

As to when to use the different auxiliaries of the potential mode see §§ 68 and 69. The conjugation with must (or ought to) is sometimes called the OBLIGATIVE MODE. The conjugation with should or would is sometimes called the CONDITIONAL MODE.]

Present Tense

(May, can, or must, with the present infinitive, be.)

1. I may, can, or must beWe may, can, or must be
2. Thou mayst, canst, or must beYou may, can, or must be
3. He may, can, or must beThey may, can, or must be

Past Tense

(Might, could, would, or should, with the present infinitive, be.)