Just two words, but they do so much. But what exactly? Here to answer that question is Dr Isabelle Burke, who has studied yeah-no in depth. She’s also going to help us with these Mailbag questions.

• Why is LIKE so resilient?
• Why can we say “I very much enjoy…” but not “I much enjoy…” or “I very enjoy…”?
• When is a loanword not a loanword?
• Do word processors have a problem with singular THEY?
• Why doesn’t English have diacritics?