English, the distinction remains in the verb "to be": I was, we were. In Dutch, it remains in the verbs of classes 4 & 5 but only in vowel length: ik brak (I broke – short a), wij braken (we broke – long ā). In German and Dutch it also remains in the present tense of the preterite presents. In Limburgish there is a little more left. E.g. the preterite of to help is (weer) hólpe for the plural but either (ich) halp or (ich) hólp for the singular. In the process of development of English, numerous sound changes and analogical developments have fragmented the classes to the extent that most of them no longer have any coherence: only classes 1, 3 and 4 still have significant subclasses that follow uniform patterns. Before looking at the seven classes individually, the general developments that affected all of them will be noted. The following phonological changes that occurred between Proto-Indo-European and Proto-Germanic are relevant for the discussion of the ablaut system. The development of grammatischer Wechsel as a result of Verner's law (the voicing of fricatives after an unstressed vowel). This created variations in the consonant following the ablaut vowel. When the zero grade appears before l, r, m or n, the vowel u was inserted, effectively creating a new "u-grade". o → a (also oy → ai, ow → au). e → i when i, ī or j followed in the next syllable. This change is known as umlaut, and was extended to affect other vowels in most later languages. ey → ī as a result of the above. e → i before m or n followed by another consonant. This had the effect of splitting class 3 into 3a and 3b. In West Germanic, the 2nd person singular past indicative uses the vowel of Part 3. Its ending is also an -i of unclear origin, rather than the expected -t < PIE *-th₂e of North and East Germanic, which suggests that this state of affairs is an innovation. Classes 1 to 6 The first 5 classes appear to continue the following PIE ablaut grades: Except for the apparent ē-grade in part 3 of classes 4 and 5, these are in fact straightforward survivals of the PIE situation. The standard pattern of PIE is represented in Germanic by classes 1, 2 and 3, with the present (part 1) in the e-grade,