In Germanic languages, weak verbs are those verbs that have a regular inflection, in which the stem of a word is not changed by ablaut. They contrast with the strong verbs, that exhibit these changes.
In most Germanic languages, the preterites and past participles of weak verbs are distinguished by a dental suffix, an inflection that contains a /t/ or /d/ sound. Not all weak verbs are regular verbs in English; some have been made irregular by eclipsis or contraction, such as hear ~ heard; while others are merely irregular due to the eccentricities of English spelling, such as lay ~ laid.
In grammar, the term weak (originally coined in German: schwach) is used in opposition to the term strong (stark) to designate a conjugation or declension when a language has two parallel systems.
Verbs with a weak radical are termed weakverbs, and form partially regular exceptions to the normal conjugation rule.
It is true that most English or German weakverbs are regular, whereas Germanic strong verbs, despite the regularity of the system, are normally taught as irregular verbs; but there are also irregular weakverbs in English and German, and in Hebrew the weakverbs are the most irregular ones.
Weakverbs should be contrasted with strong verbs, which form their past tenses by means of ablaut.
Weakverbs are often thought of as having a regular inflection, but not all weakverbs 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 linguistics, a participle is an adjective derived from a verb.