Longman Advanced Grammar Here

: Highlighting clauses (relative, conditional, etc.) and their relationships.

: Interactive versions of "Exercise 1" in the text, where learners must explain subtle differences in meaning between similar sentences (e.g., She must have been happy vs. She had to be happy ). Longman Advanced Grammar

P is for Prescriptive | An A-Z of ELT - Scott Thornbury's blog : Highlighting clauses (relative, conditional, etc