For a fuller table, see Indo-European sound laws. The following table presents a comparison of conjugations of the thematic present indicative of the verbal root * of the English verb "to bear" and its reflexes in various early attested IE languages and their modern descendants or relatives, showing that all languages had in the early stage an inflectional verb system. While similarities are still visible between the modern descendants and relatives of these ancient languages, the differences have increased over time. Some IE languages have moved from synthetic verb systems to largely periphrastic systems. In addition, the pronouns of periphrastic forms are in brackets when they appear. Some of these verbs have undergone a change in meaning as well. Today, Indo-European languages are spoken by 3.2 billion native speakers across all inhabited continents, the largest number by far for any recognised language family. Of the 20 languages with the largest numbers of native speakers according to "Ethnologue", 10 are Indo-European: Spanish, English, Hindustani, Portuguese, Bengali, Russian, Punjabi, German, French, and Marathi, accounting for over 1.7 billion native speakers. Additionally, hundreds of millions of persons worldwide study Indo-European languages as secondary or tertiary languages, including in cultures which have completely different language families and historical backgrounds—there are between 600 million and one billion L2 learners of English alone. The success of the language family, including the large number of speakers and the vast portions of the Earth that they inhabit, is due to several factors. The ancient Indo-European migrations and widespread dissemination of Indo-European culture throughout Eurasia, including that of the Proto-Indo-Europeans themselves, and that of their daughter cultures including the Indo-Aryans, Iranian peoples, Celts, Greeks, Romans, Germanic peoples, and Slavs, led to these peoples' branches of the language family already taking a dominant foothold in virtually all of Eurasia except for swathes of the Near East, North and East Asia, replacing many (but not all) of the previously-spoken pre-Indo-European languages of this extensive area. However Semitic languages remain dominant in much of the Middle East and North Africa, and Caucasian languages in much of the Caucasus region. Similarly in Europe and the Urals the Uralic languages (such as Hungarian, Finnish, Estonian etc) remain, as does Basque, a pre-Indo-European Isolate. Despite being unaware of their common linguistic origin, diverse groups of Indo-European speakers continued to culturally dominate and often replace the indigenous languages of the western two-thirds of Eurasia.