noun or preposition and indicate verbal and prepositional objects or possession of nouns. The first-person singular pronoun has a different enclitic form used for verbs ( /-nī/) and for nouns or prepositions ( /-ī/ after consonants, /-ya/ after vowels). Nouns, verbs, pronouns and adjectives agree with each other in all respects. However, non-human plural nouns are grammatically considered to be feminine singular. Furthermore, a verb in a verb-initial sentence is marked as singular regardless of its semantic number when the subject of the verb is explicitly mentioned as a noun. Numerals between three and ten show "chiasmic" agreement, in that grammatically masculine numerals have feminine marking and vice versa. Verbs Verbs in Literary Arabic are marked for person (first, second, or third), gender, and number. They are conjugated in two major paradigms (past and non-past); two voices (active and passive); and six moods (indicative, imperative, subjunctive, jussive, shorter energetic and longer energetic), the fifth and sixth moods, the energetics, exist only in Classical Arabic but not in MSA. There are also two participles (active and passive) and a verbal noun, but no infinitive. The past and non-past paradigms are sometimes also termed perfective and imperfective, indicating the fact that they actually represent a combination of tense and aspect. The moods other than the indicative occur only in the non-past, and the future tense is signaled by prefixing or onto the non-past. The past and non-past differ in the form of the stem (e.g., past vs. non-past ), and also use completely different sets of affixes for indicating person, number and gender: In the past, the person, number and gender are fused into a single suffixal morpheme, while in the non-past, a combination of prefixes (primarily encoding person) and suffixes (primarily encoding gender and number) are used. The passive voice uses the same person/number/gender affixes but changes the vowels of the stem. The following shows a paradigm of a regular Arabic verb, 'to write'. In Modern Standard, the energetic mood (in either long or short form, which have the same meaning) is almost never used. Derivation Like other Semitic languages, and unlike most other languages, Arabic makes much more use of nonconcatenative morphology (applying many templates applied roots) to derive words than adding prefixes or suffixes to words. For verbs, a given root can occur in many different derived verb stems (of which there are about fifteen), each with one or