How are humans able to speak inside of their minds (have an inner speech?)

Question: How are humans able to speak inside of their minds (have an inner speech?)
- Keywords:
  inner speech,
  speech
Asked by anon-361762 on 30 Mar 2023.
- Eileen Xu answered on 30 Mar 2023:
  
  I don’t think we know the answer to that yet! It’s really exciting though, and what’s stranger is that not everybody has that internal monologue either!

Question: How are humans able to speak inside of their minds (have an inner speech?)