Formal terms:
* Illiterate: This term refers to someone who cannot read or write.
* Non-literate: This term is similar to illiterate but sometimes preferred as it is less judgmental.
Informal terms:
* Functionally illiterate: This term refers to someone who has basic literacy skills but struggles to read and write at a level needed for everyday life.
* Unlettered: This term emphasizes the lack of education and formal learning.
* Unskilled in writing: This is a more neutral term that focuses on the specific skill of writing.
Other possibilities:
* Dyslexic: This term refers to someone who has a learning disability that makes it difficult to read and write.
* Aphasic: This term refers to someone who has lost their ability to speak or write due to a brain injury.
It's important to be sensitive when discussing someone's ability to write. Using the term "illiterate" can be seen as offensive or stigmatizing. It's often better to use more neutral language, like "unable to write," or to ask for clarification about the reason for their inability to write.