Germanic weak verb

In Germanic languages, weak verbs are those verbs that form their preterites and past participles by means of a dental suffix, an inflection that contains a /t/ or /d/ sound. For example:

• to love - loved
• to say - said
• to send - sent
• to lean - leaned or leant

In English, the dental is a /d/ after a voiced consonant or vowel, and a /t/ after a voiceless consonant, though English uses the spelling in <d> in most cases, regardless of pronunciation. In German and Dutch final consonants are never voiced, so the pronunciation /d/ does not occur. Nevertheless, Dutch distinguishes the letters <d> and <t> regularly as though the originally voiced consonants were still voiced. (See Dutch spelling for the 't kofschip rule.) German on the other hand knows only spellings in <t>.

The weak conjugation of verbs is an innovation of Proto-Germanic. The origin of the dental suffix is uncertain. One theory is that it evolved out of a periphrastic construct with the verb to do, eg I love did > I loved (Germanic *lubōjana dēdo > *lubōdo, hence Old English lufode). This would be analogous to the way that in Modern English we can form a past tense with "did": I did love. Another theory is that it came from a past participle ending, a final *-daz from IE *-tos (cf Latin amatus), with personal endings added to it at a later stage. Both theories are disputed because of their inability to explain all the facts.

Weak verbs should be contrasted with strong verbs, which form their past tenses by means of ablaut. All the original Indo-European verbs which came into Germanic as verbs were once strong. However, as the ablaut system is no longer productive, all new verbs in Germanic languages are weak, and the majority of the original strong verbs have become weak by analogy. In some cases a verb has become weak in the preterite but not in the participle, or (rarely) vice versa. These verbs may be thought of as "semi-strong" (not a technical term). Dutch has a number of examples of this:

• wassen waste gewassen ("to wash")
• jagen joeg gejaagd ("to hunt")

In the medieval Germanic languages, a number of different classes of weak verbs had to be distinguished, according to the consonants in the stem...

In the modern languages, these distinctions have mosly been levelled. The regular weak verbs conjugate as follows:

	English	Dutch	German	Swedish	Yiddish
Infinitive	to work	werken	wirken	verka	(verkn) װערקן
Present	I work you work he works we work you work they work	ik werk jij werkt hij werkt wij werken jullie werken zij werken	ich wirke du wirkst er wirkt wir wirken ihr wirkt sie wirken	jag verkar du verkar han verkar vi verkar ni verkar de verkar	(ikh verk) איך װערק (du verkst) דו װערקסט (er verkt) ער װערקט (mir verkn) מיר װערקן (ir verkt) איר װערקט (zey verkn) זי װערקן
Preterite	I worked you worked he worked we worked you worked they worked	ik werkte jij werkte hij werkte wij werkten jullie werkten zij werkten	ich wirkte du wirktest er wirkte wir wirkten ihr wirktet sie wirkten	jag verkade du verkade han verkade vi verkade ni verkade de verkade	(not used)
Past participle	worked	gewerkt	gewirkt	verkat	(geverkt) געװערקט

Weak verbs are often thought of as having a regular inflection, but not all weak verbs are regular verbs; some have been made irregular by ellipsis or contraction, such as hear ~ heard; while others are merely irregular due to the eccentricities of English spelling, such as lay ~ laid. In German, verbs ending in -eln or -ern have slightly different inflection patterns. There are many other examples. The Preterite-present verbs are in a sense weak verbs with very significant irregularities; but usually they are not bracketed under weak verbs.

One particularly interesting category of irregular weak verb is the so-called rückumlaut verb. This is discussed in the article on umlaut under the section "Umlaut in Germanic verbs". An original -j- in the inflection caused the whole of the present stem (including the infinitive) to experience a fronting of the stem vowel, though the past tense retains the back vowel. These verbs typically also experience a consonant change. Examples are:

• English: think thought
• German: denken dachte gedacht

Some grammar books use the term "mixed verb" to describe these. This rests on the misconception that these verbs display both ablaut and a dental suffix, and are therefore at once strong and weak. But the vowel change is not ablaut.

The term "weak verb" was originally coined by Jakob Grimm and in his sense refers only to Germanic philology. However, the term is sometimes applied to other language groups to designate phenomena which are not really analogous. For example, Hebrew irregular verbs are sometimes called weak verbs because one of their radicals is weak.

For other aspects of the verb in Germanic languages see the overview article Germanic verb.