II. Condition

Note. The subjunctive in these concessive and conditional uses is really the same as that in exhortations ([§ 278]). “Try [we] as we may” means literally, “Let us try as hard as we can,” and this has the force of “However hard we try” or “Although we try ever so hard.”

282. After as if (as though), the past subjunctive is used.

283. The subjunctive may express not what is or was, but what would be or would have been, the case.

This construction is old-fashioned. Modern English commonly uses should (or would) be, should (or would) have been, instead.

284. The subjunctive is occasionally used after that, lest, before, until, etc., in subordinate clauses referring to the future and commonly expressing purpose or expectation.