There are similarities across most languages. Language universals are the characteristics and subsystems that are common to all languages. A speaker of any language employs these features of language for communicative purposes. The processes of reading and concepts about the relationship between speech and print that apply to written languages are called literacy universals.
Both language and literacy universals are learned and applied as biliteracy develops, through a process of cross-linguistic transfer. By intentionally providing a comprehensible connection between languages, explicit teaching for transfer promotes metacognitive and Metalinguistic Skills and Awareness development as students are taught to think about the languages they are learning and using. Within the language universals, there are several language subsystems, including phonology, morphology, grammar, syntax, semantics, and pragmatics.