First, a quick clarification. Mastermind Use of English is a well-known textbook series (often by Andrew Betsis) designed for C2-level learners. The Mini Companion is a supplementary booklet—often available as a scanned PDF—that acts as an answer key and glossary.
, if you plan to use it as a crutch to avoid thinking through difficult grammar.
Don't just read the glossary. Use the PDF’s search function to find the original exercise where that word appeared. Context is king.
Is the Mastermind Use of English Mini Companion PDF Your Secret Weapon for C2 Proficiency?