The term verbal stem is a theoretical construct that refers to the underlying phonological form of the verb, as listed in the mental lexicon. For example, the stems of the verbs schoppen'to kick' and schrobben'to scrub' have the phonemic representations /sxɔp/ and /sxrɔb/, with respectively a voiceless and a voiced final plosive, despite the fact that, when no morphological material is attached to the stem, these strings would both be phonetically realized with a voiceless plosive as result of the Dutch rule that word-final consonants be devoiced; see Booij (1995) for details. Table (111) shows this for all Dutch obstruents, which, with the exception of the velar plosive /k/, all form systematic phonemic oppositions with respect to voice. The table also provides the orthographic representations that can be found; we will return to these in what follows.

The postulation of the phonemic representations in the second column of Table (111) is motivated by the fact that these play an important role in the pronunciation (as well as the spelling) of plural present-tense forms, regular past-tense forms, infinitives and participles. Table (112) illustrates this for infinitives, which are homonymous to plural present-tense forms, but we will postpone discussion of the other cases to the relevant sections below.

      The final column in Table (111) shows that in the case of plosives, the spelling is fully determined by the postulated phonemic representations; the underlying voiced /b/ and /d/ are represented by the letters "b" and "d", even if they are devoiced in speech, as in the (a)-, (b)- and (e)-examples in (113).

This does not hold for the fricatives /v/ and /z/, which are only represented by the letters "v" and "z" if they are in intervocalic position, that is, followed by the suffix -en (in infinitives and present plural forms) or -end (in present participles), as in the (d)- and (f)-examples in (114). In all other cases they are represented by the letters "f" and "s"; this includes cases in which they are voiced in speech, such as the past tenses kliefde'cleaved' and loosde'drained away' in the (c)-examples, which are pronounced as, respectively, [klivdə] and [lozdə].

      Verbal stems, of course, need not end in an obstruent but can also end in a nasal (/n/, /m/ and /ŋ/), a liquid (/l/ and /r/) or a glide (/ʋ/ and /j/).

Verbs that end in a short vowel do not occur, which need not surprise us because Dutch has a general ban on short vowels in open syllables. Stems that end in a long vowel do occur but are relatively rare; there is a small number of commonly used verbs like gaan'to go', staan'to stand', slaan'to hit', zien'to see', and doen'to do' (and other formations like verslaan'to beat' that seem to be morphologically derived from these simple verbs). In addition to these simple verbs, the Van Dale dictionary gives an extremely small number of other cases like sleeën'to sledge', spieën'to fix with a pin', shampooën'to clean with shampoo', fonduen'to eat fondue', boeën'to yell boo', heuen'to rush', and keuen'to play billiards', which all seem to be denominal. The first set of verbs we will call contraction verbs, given that they form their infinitive/plural present-tense form by means of a reduced version of the suffix -en: -n. The denominal verbs differ from the simple verbs that end in a vowel in that they take the full form -en.

      The discussion above has shown that, apart from the small set of contraction verbs, simple verbs never end in a short or long vowel. There are however, many cases in which the stem ends in a diphthong; some examples are given in (117). That diphthongs are easily possible need not surprise us because (115c) has shown that stems may also end in a glide.