First, let's review some of the conditional particles that you can use to express a hypothetical idea. Of course, you have si (if) and nisi (if not; unless), for straightword conditions. In addition, there is a whole series of concessive participles that are very useful that express the idea of "even it" or "even though" in English: etsi, tametsi, etiamsi, licet and quamvis.
So, you can take any one of those hypothetical participles and use them without a verb to express a hypothetical idea - all you need is a noun or adjective or prepositional phrase, something that will link the hypothetical idea to the main sentence.
Here's an example. When I saw this word list - equus - res - discipulus - iste - animal - I knew I wanted to say something about how the horse is a good pupil, while the donkey (who is often the opposite of the horse in the world of proverbs) is not a good pupil. Here's how I described the donkey: asinus nihil discit, etiamsi verberatus, "the donkey doesn't learn anything, even if (he is) beaten." Without having to worry about what kind of verb to use there, I was able to use an adjective (a participle, as it turns out, but any adjective will do) in order to express a hypothetical idea. If you want to see how the whole thing turned out, here it is.