Blasen has gone weak. 7e (ō-ē-ō) is reduced to one single verb: ropen. This subgroup had become similar to 7b already in Old Saxon. North Germanic Changes from Proto-Germanic to Old Norse: ē > ā a-mutation: u > o when a follows in the next syllable. This affected the past participles of classes 2–4. However, an intervening m or n + consonant blocked this, so the past participle of class 3a kept u. Extension of umlaut to back vowels, causing it to apply also to verbs of class 6. v- is lost before u or o. -n is lost from the infinitive and many inflectional endings. Voiced plosives (but not fricatives) are devoiced word-finally. In Old West Norse, this later causes loss of a preceding nasal. Breaking of e to ja in most environments, and of eu to jū/jō. In class 7, several reduplicated verbs are retained: róa reri ("to row"), sá seri ("to sow"), snúa sneri ("to turn"). Danish Class 1 This class has generalised part 2 over part 3 creating a past tense in 'e'. The class can be split up by the different vowels the supine can take: with 'e' supine: , , , , , , , , , , , , , , , , , / , , , . with 'i' supine: , , , , , , , . Class 2 This class has generalised part 2 over part 3 creating a past tense in 'ø'. The class can be split up by the different vowels the supine can take: with 'u' supine: , , , , . with 'y' supine: , , , , , , , , . with 'ø' supine: , , , , . Anomalous: – frøs – frosset – fløj – fløjet – løj – løjet Class 3 This class has disintegrated into a number of smaller subgroups, all its members have generalised part 2 over part 3 creating a past tense with 'a'. class 3a: with 'i' in present tense and 'u' supine: , , , , , , , , , , , , . with 'i' in present tense and 'i' supine: , , . with 'y' in present tense and 'u' supine: , . class 3b: with 'æ' in present tense and 'u' supine: (strong forms are archaic), , , , . with 'æ' in present tense and 'æ' supine: , , Class