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Search concise B2 rules, vocabulary and speaking phrases without leaving the course to hunt through past lessons.
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Clauses & Linking
Quick rule
Defining = essential, no commas, 'that' allowed. Non-defining = extra information, commas, never 'that'.
The app that everyone recommends drains the battery.
Lisbon, which we visited in May, is far cheaper off-season.
That's the engineer whose patent started the whole thing.
This is the point where most learners stop.
Common mistake
✗ My brother, that lives in Rome, is a chef. → ✓ My brother, who lives in Rome, is a chef.
Short practice
Join: 'This is the flat. We rented it last year.' → This is the flat (that) we rented last year.