Why can't Chewbacca speak Galactic Basic (English)?

It clearly states in the factbook 'Star Wars: Absolutely Everything You Need to Know' that Wookiees cannot speak Basic (e.g. English) for physiological reasons. "Strange but true: Wookiees cannot speak Basic because of their strange vocal chords - but they can understand it. read more

He doesn't talk Galactic Basic because he can't, physically. He understands it, as he is very smart, but he needs to use ROARS to communicate as that's how he physically communicates. read more

Galactic Basic Standard (or Galactic Basic, Galactic Standard, Galaxy Standard or just Basic) was the most prevalent language in the galaxy. Talking about Chewbacca, he fully understands Basic (because Han has never roared to him). read more