Old English give certain evidence of an influence on syntax. The change to Old English from Old Norse was substantive, pervasive, and of a democratic character. Old Norse and Old English resembled each other closely like cousins and with some words in common, they roughly understood each other; in time the inflections melted away and the analytic pattern emerged. It is most "important to recognize that in many words the English and Scandinavian language differed chiefly in their inflectional elements. The body of the word was so nearly the same in the two languages that only the endings would put obstacles in
Old English grammar known as "ablaut". In this form of conjugation, the stem of the word changes to indicate the tense. Verbs like this persist in modern English; for example "sing, sang, sung" is a strong verb, as are "swim, swam, swum" and "choose, chose, chosen". The root portion of the word changes rather than its ending. In Old English, there were seven major classes of strong verb; each class has its own pattern of stem changes. Learning these is often a challenge for students of the language, though English speakers may see connections between the old verb classes and their modern forms.