•       The two languages are represented somehow in separate systems in the mind. Separate phonemic systems for L1 & L2.

    This hypothesis suggests that the bilingual’s two languages are represented in a unified cognitive system.

•       The idea of having separated systems would explain the loss of just one of the languages known by bilinguals if the individual has a lesion.

•       In the bilingual brain there are as many systems as many languages bilingual people know.

•       In the bilingual brain there is a larger system which contains each language in

•       This theory does not explain how bilingual people mix languages in the same sentence, and it is true that they do it.

•       In the bilingual brain there is a larger system which contains each language in smaller sub-systems.

  In these separate systems the brain stores all linguistic information that is not common to both languages.

•       In the bilingual brain, there are as many systems as many languages bilingual people know.

   Children can understand and identify who in the house speaks which language.

·       It is difficult for bilinguals to choose the correct language to communicate within a specific situation.

·       Bilinguals are capable of developing vocabulary and mixing words (code-switching) in two languages but get confused.

•       acquires the two languages in different contexts.

•       learns both languages from native speakers at home, one from your mother and the other from your father, for instance.

•       is proficient in one of the two languages.

·       characterize simultaneous bilingualism in early childhood (before the age of three years).

·       means that the words of the weaker language are interpreted through the words of the stronger or dominant language.

·       belong to two separate or independent systems. When words are alike in the two languages, both have (slightly) different meanings and they can refer to different concepts.

•       the second language is learned with the help of the first or dominant language.

•       characterize simultaneous bilingualism in early childhood (before the age of three years). 

•       the mental representation of knowledge about the two languages is thought to be relatively independent.

•       the last learned language would be the first to be lost.

•       the first learned language would be the first to be lost.

•       the last learned language would be the last to be lost.

•       the site of the lesion, the severity of the impact.

•       the age of the patient and the success of the treatment methods.

•       Both factors mentioned in this question