diff --git a/aider/website/docs/faq.md b/aider/website/docs/faq.md
index 003c61ecd..9b67295e6 100644
--- a/aider/website/docs/faq.md
+++ b/aider/website/docs/faq.md
@@ -217,6 +217,18 @@ by doing something like `git blame` on the repo,
 and counting up who wrote all the new lines of code in each release.
 Only lines in source code files are counted, not documentation or prompt files.
 
+## Why is the LLM speaking to me in an unexpected language?
+
+Aider goes to some effort to prompt the model to use the language that is configured
+for your system.
+But LLMs aren't fully reliable, and they sometimes decide to speak in
+an unexpected language.
+Claude is especially fond of speaking French.
+
+You can explicitly set the language that aider tells the model to use with
+`--chat-language <language>`.
+But the LLM may not comply.
+
 ## Can I share my aider chat transcript?
 
 Yes, you can now share aider chat logs in a pretty way.