What is the characteristic of sequential bilingualism?

Sequential bilingualism is characterized by the acquisition of a second language after the first language has been established, typically after the age of 3. This process involves a sequence where the first language is learned first, followed by the introduction of a second language later. Individuals who are sequential bilinguals typically develop proficiency in the first language before transitioning to learning the second one. This distinction is important as it impacts language development stages and the cognitive processes associated with learning a second language.

In contrast, learning two languages simultaneously is indicative of simultaneous bilingualism. Fluency in both languages from an early age often describes early simultaneous bilinguals, and while formal education can facilitate language learning, it is not a defining characteristic of sequential bilingualism, as many learners acquire a second language in informal settings or through everyday interactions.