As mentioned above, not all ELLs are the same. ELLs may enter a school with vastly dierent educational backgrounds. Some enter U.S. schools with a strong foundational knowledge in their rst language. is means that they may have had schooling in their rst language, have literacy skills in their rst language, and/or have developed social everyday language competency as well as academic prociency in their rst language. Other ELLs may have had less or even no academic schooling in their rst language. Many ELLs, especially refugees, may have attended school in their homeland only for it to have been interrupted by famine or war, or for other socioeconomic or political reasons. Some ELLs arrive in the United States with their families at a very young age and, although they speak their rst language at home, they may have never developed reading or writing prociency in it. As will be discussed in the next chapter, it is of great importance to uncover the nature of an ELL’s rst language development since this has a profound bearing on how an ELL manages to acquire English.