Дефектные глаголы: неполная парадигма спряжения.

Verb with incomplete conjugation

In linguistics, a defective verb is a verb that either lacks a conjugated form or entails incomplete conjugation, and thus cannot be conjugated for certain grammatical tenses, aspects, persons, genders, or moods that the majority of verbs or a "normal" or regular verb in a particular language can be conjugated for. That is to say, a defective verb lacks forms that most verbs in a particular language have.

The most commonly recognized defective verbs in English are auxiliary verbs—the class of preterite present verbs—can/could, may/might, shall/should, must, ought, and will/would (would being a later historical development). Though these verbs were not originally defective, in most varieties of English today, they occur only in a modal auxiliary sense. However, unlike normal auxiliary verbs, they are not regularly conjugated in the infinitive mood. Therefore, these defective auxiliaries do not accept each other as objects. Additionally, they do not regularly appear as participles. For example, can lacks an infinitive, future tense, participle, imperative, and gerund. The missing parts of speech are instead supplied by using the appropriate forms of to be plus able to. So, while I could write and I was able to write have the same meaning, I could has two meanings depending on use, which are I was able to or I would be able to. One cannot say *I will can, which is instead expressed as I will be able to. Similarly, must has no true past tense form, this instead being supplied by had (the past tense of have), and "to have to" in the infinitive, an example of composite conjugation. The past tense expressing the obligatory aspect of must is expressed as "had to", as in He had to go. "Must have", on the other hand, expresses probability or likelihood in modern English; for example, "If that's thunder, there must have been lightning." Some verbs are becoming more defective as time goes on; for example, although might is etymologically the past tense (preterite) of may, it is no longer generally used as such (for example, *he might not go to mean "he was forbidden to go"). Similarly, should is no longer used as the past of shall, but with a separate meaning indicating possibility or moral obligation. (However, the use of the preterite form should as a subjunctive form continues, as in If I should go there tomorrow, , which contrasts with the indicative form I shall go there tomorrow.) The defective verb ought was etymologically the past tense of owe (the affection he ought his children), but it has since split off, leaving owe as a non defective verb with its original sense and a regular past tense (owed). Beyond the modal auxiliaries, beware is a fully defective verb in current Modern English: its only, unmarked form is regularly used (in simple aspect, active voice) in the infinitive (I must beware of the dog), imperative (Beware of the dog, [Let the] buyer beware) and subjunctive (She insists that he beware of the dog), but too much of the finite indicative mood is formally lacking (all simple past *bewared, one simple present *bewares, all aspects *am bewaring, etc.). The word begone is similar: any usage other than as an imperative is highly marked. Another defective verb is the archaic quoth, a past tense which is the only surviving form of the verb quethe, "to say" (related to bequeath).

In Arabic, defective verbs are called أفعال جامدة (lit., ). These verbs do not change tense, nor do they form related nouns. A famous example is the verb [[wikt:ليس , though it is not the only auxiliary verb that exhibits this property. Some Arabic grammarians argue that [[wikt:دام#Arabic (as an auxiliary verb) is also completely defective; those who dispute this claim still consider it partially defective. Some other partially defective verbs are [[wikt:فتئ and [[wikt:زال , which have neither an imperative form nor an infinitive form when used as auxiliary verbs.

In Catalan, defective verbs are usually defective for semantic reasons. Due to their impersonal nature, haver hi and caldre are only used in the third person. The implicit repetition intrinsic to the meaning of soler results in it only having forms in the present and imperfect tenses. Verbs pertaining to meteorological phenomena, such as ploure, can only be conjugated in the third person singular, although a third person plural form is also possible when used with a metaphorical sense. Additionally, lleure is used only in the third person, while dar lacks present tense forms, with the exceptions of the first person plural and second person plural. Defective verbs in Catalan can generally also be used in the impersonal forms of the infinitive, gerund, and past participle.

At least one Finnish verb lacks the first infinitive (dictionary/lemma) form. In Finnish, "kutian helposti" ("I'm sensitive to tickling") can be said, but for the verb "kutian" (here conjugated in singular first person, present tense) there is no non conjugated form. Hypothetically, the first infinitive could be "kudita", but this form is not actually used. Additionally, the negative verb (ei, et, en, emme ) has neither an infinitive form nor a 1st person singular imperative form.

In contemporary German, the verb erkiesen, which means "to choose/elect" (usually referring to a person chosen for a special task or honour), is only used in the past participle (erkoren) and, more rarely, the past tense (ich erkor etc.). All other forms, including the infinitive, have long become obsolete and are now unknown and unintelligible to modern speakers. It remains commonplace in the closely related Dutch language as verkiezen; for example, Verkiezingen in Nederland (Elections in the Netherlands).

"No single Greek verb shows all the tenses", and "most verbs have only six of" the nine classes of tense systems, and "[s]carcely any verb shows all nine systems". The verb χρή (khrē, 'it is necessary'), only exists in the third person singular present and imperfect ἐχρῆν / χρῆν (ekhrēn / khrēn, 'it was necessary'). There are also verbs like οἶδα (oida, 'I know'), which use the perfect form for the present and the pluperfect (here ᾔδη ēidē, 'I was knowing') for the imperfect. Additionally, the verb εἰμί (eimi, 'I am') only has a present, a future and an imperfect – it lacks an aorist, a perfect, a pluperfect and a future perfect.

Some Hungarian verbs have either no subjunctive forms or forms which sound uncommon to native speakers; for example, csuklik See also a short summary about them in the English language Wiktionary.

Arsa can be used only in the past or present tense. The copula is lacks a future tense, an imperative mood, and a verbal noun. It has no distinct conditional tense forms either, but conditional expressions are possible, expressed using past tense forms; for example Ba mhaith liom é, which can mean both and The imperative mood is sometimes suppletively created by using the imperative forms of the substantive verb bí. Future tense forms, however, are impossible and can only be expressed periphrastically. There is also dar , a temporally independent verb that always appears in combination with the preposition le.

Korean has several defective verbs. (말다 ) may only be used in the imperative form or in the hortative form, after an 'action verb + 지 ' construction. Within this scope it can still conjugate for different levels of politeness, such as 하지 마! , in contrast with 하지 마십시오 Also, 데리다 is only used as 데리고 , 데리러 , or 데려 in some compound forms.

Widać and słychać are both highly defective in Polish. The only forms of these verbs that exist are the infinitives. They both work as impersonal verbs in a visible or audible situation that does not require another verb (although may have one), and they have no distinction between singular and plural. For example Widać blask wśród drzew or Jego głos słychać w całym domu .

A large number of Portuguese verbs are defective in person; that is, they lack the proper form for one of the pronouns in some tense. The verb colorir ("to color") has no first person singular in the present, thus requiring a paraphrase, like estou colorindo ("I am coloring") or the use of another verb of a similar meaning, like pintar ("to paint").

Some Russian verbs are defective, in that they lack a first person singular non past form: for example, победить , убедить , дудеть These are all verbs whose stem ends in a palatalized alveolar consonant; they are not a closed class, but include in their number neologisms and loanwords such as френдить Where such a verb form would be required, speakers typically substitute a synonymous verb (Я выиграю), or use a periphrastic construction involving nominalization and an additional verb (Я одержу победу). Also the word могу is used: (Я) смогу победить, (я) смогу убедить. Many experiential verbs describe processes that humans cannot generally undergo, such as пригореть , куститься , and протекать —are ordinarily nonsensical in the first or second person. As these forms rarely appear, they are often described as "defective" in descriptions of Russian grammar. However, this is a semantic constraint rather than a syntactic one; compare the classic nonsensical but grammatical sentence Colorless green ideas sleep furiously, or more directly, the English phrase I am raining. First and second person forms of these verbs do see use in metaphor and poetry.

The auxiliary verb måste lacks an infinitive, except in Swedish dialects spoken in Finland. Also, the verb is unique in that the form måste serves as both a present and past form. The supine måst is rare.

While the Turkish copula is not considered a verb in modern Turkish, it originated as the defective verb imek — which is now written and pronounced as a suffix of the predicate. İmek and the suffixes derived from it exist in only a few tenses; it is replaced by negative değil in the tenses originally supplied by imek, and remaining forms by olmak otherwise. The verb can be conjugated only in certain tenses: past idi, inferential perfective imiş, conditional ise, and (non finite) personal past participle idük (usable with possessive suffixes, notice the form was irregular).

Ukrainian Verbs ending in вісти (for example, розповісти and відповісти ) lack imperative mood forms; imperfective verbs are used instead (for example, відповідай).

Welsh has several defective verbs, a number of which are archaic or literary. Some of the more common ones in everyday use include dylwn ("I should/ought"), found only in the imperfect and pluperfect tenses, meddaf ("I say"), found only in the present and imperfect, and geni ("to be born"), which only has a verb noun and impersonal forms; for example, Ganwyd hi (She was born, literally "one bore her"). Common defective verbs in the spoken language are eisiau (pronounced, and often spelt, as isio or isie) and angen which mean 'to want' and 'to need' respectively; both are in fact nouns but are used in speech as if they were verb nouns though they do not take the preceding yn, compare dw i'n canu 'I sing' vs. dw i eisiau 'I want'. The literary language would use these as nouns and not as defective verbs; for example, mae eisiau arnaf 'I want', literally 'there is a want on me'.