Also, there is no imperfect subjunctive, optative or imperative. The subjunctive (or conditional) and the imperative moods have three tenses. Proto-Germanic verbs have three moods&colon; indicative, subjunctive and imperative. There were three moods&colon; indicative, subjunctive (developed from the PIE optative mood) and imperative. There is also some irregularity in certain verbs in the subjunctive. The auxiliary verbs may and let are also used often in the subjunctive mood. The original Indo-European inventory of moods consisted of indicative, subjunctive, optative, and imperative. Subjunctive conditionals are familiar from ordinary language. Arabic, however, is an example of a language with distinct subjunctive, imperative and jussive conjugations. The "-g-" is present in the present subjunctive of such verbs. The optative is generally built by adding "i" onto the subjunctive stem. There are a number of preverbal particles marking the negative, interrogative, subjunctive, relative clauses, etc. It marks the following verb as being in the subjunctive mood. The polite plural is identical to the Present Subjunctive. They inflect for the present and past tense and the imperative, subjunctive, and indicative mood.