There are specific verbs which don't take the potential form (offhand I remember , which changes to , and , which you can circumvent by using . Naturally, can't be put in the potential form either, due to recursion.). Other than that, I don't recall any verbs that are prohibited from using specified forms. Transitivity affects particle usage, but all of the verb forms remain available. In the case of intransitives and the imperative you can think of it as an order to put things in the state dictated by the verb (e.g. = "get yourself gone/make yourself scarce"; = "rise up!").