Most people who know ASL can also communicate in English, but language skills are a spectrum and some people may know enough to get by in daily life, but may no

Most people who know ASL can also communicate in English, but language skills are a spectrum and some people may know enough to get by in daily life, but may not know enough English to understand more complicated topics. It's really no different than a native Spanish speaker living in the United States. Some may only know a basic level of English while others may be equally comfortable in both languages. This isn't even unique to the Deaf community. Something like 15 to 20 percent of the general population are considered functionally illiterate.