Working through official CAE past papers systematically, a pattern becomes hard to miss: the same handful of words keep showing up, paper after paper. Not synonyms of each other. The same words.
Despite. Whereas. Unless. Provided. In case. No matter. Not every single time, but often enough that it stops looking like coincidence once you actually write it down.
Why this isn't really a surprise, once you think about what Open Cloze tests
Reading and Use of English Part 2 fills gaps with function words: connectors, prepositions, articles, quantifiers, relative pronouns. It's explicitly not testing vocabulary range the way Part 1 does. There's no lexical choice involved, no near synonym competing with the right answer. There's a grammatical slot, and a closed, fairly small set of words that can fill it correctly.
That constraint is exactly why the same words recur. English doesn't have unlimited ways to signal concession, condition, or contrast at C1 level. If a text needs a concessive link, the realistic candidates are despite, in spite of, although, even though, whereas, while. If it needs an unusual conditional, the field narrows further: provided, providing, unless, as long as, in case. Cambridge isn't recycling vocabulary out of laziness. The construct itself has a limited word bank, so overlap across sessions is close to guaranteed rather than accidental.
What the tracker actually shows
We're not claiming exact frequency percentages here, because that would need a proper count across every paper in the archive, and the tracker wasn't built for that kind of analysis. What candidates and C2 consultants who analyze past papers regularly notice, consistently, is which words come up again repeatedly across test papers. That pattern is the useful part, not a precise ranking.
The three families that keep appearing
Concession words show up constantly: despite, in spite of, whereas, while, even though. They're common because Part 2 texts are often built around some kind of contrast, an argument with a twist in it, and a text needs a connector to carry that twist grammatically.
Restrictive condition words are the second cluster: unless, provided, providing, as long as, in case. These test something quite specific, a conditional relationship that isn't the plain if of B1 grammar, and that specificity is probably why Cambridge returns to them. There's no simpler paraphrase available. If the gap needs unless, nothing else quite does the job, which makes it a clean, unambiguous test item.
The third is less obviously a family and more a set of stragglers that behave the same way: no matter, let alone, such, so, whatever their exact grammatical role in a given sentence. They tend to appear in the second half of a paper, often in a sentence that's doing something slightly more complex than the ones around it.
Why memorizing the list still doesn't work
Here's the part that trips candidates up even after they've seen this pattern pointed out to them. Knowing that despite tends to appear doesn't tell you when to write despite instead of although in a given gap, and that's the actual skill being tested. Both words handle concession. Only one of them fits the grammar of the specific sentence in front of you, because despite takes a noun or a gerund and although takes a full clause.
A candidate who has memorised "despite, whereas, unless, these come up a lot" without understanding why each one is grammatically distinct from its closest neighbour is going to guess wrong about half the time anyway. The list is a starting point for noticing, not a shortcut around actually learning the grammar behind each word.
What tends to work better, based on real practice sessions, is going through five or six real Part 2 texts and, for every gap filled by one of these recurring words, checking what comes immediately before and after it. Despite is almost always followed by a noun phrase or an ing form. Although is almost always followed by a subject and a conjugated verb. That pattern holds regardless of the topic of the passage, and it's the pattern an exam is actually checking, not whether the student recognizes the word in isolation.
Next time you sit down with a Part 2 past paper, don't just check whether your answer was right. Circle every gap filled by a word from this rough list, concession, restrictive condition, or the odd one out group, and write down what comes right after it in the sentence. After five or six papers the grammar behind each word tends to click in a way that a vocabulary list never quite manages.
Sources
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