Exam vocabulary through novels: reading for IELTS, TOEFL and Cambridge
Exams test the vocabulary of educated English and the stamina to read long passages quickly; novels build both, and a word list on its own builds neither. Read at B2 or above, keep a list such as the Oxford 3000 beside the book, and save the list words you meet.
What the reading paper actually tests
IELTS Academic gives you three passages of around 900 words each in an hour. TOEFL gives you academic passages with ten questions each. Cambridge B2 First and C1 Advanced give you long texts with detail and inference questions. In every case the two skills that decide the score are the same: knowing enough words to read without stopping, and being able to read 2,500 words with attention when you are tired. Practice tests measure these skills; they do not build them.
Why novels build them
A novel is a long text you want to finish. It trains the stamina exams demand without anyone making you. And the vocabulary of classic fiction overlaps heavily with the vocabulary of exam passages: the words for describing people, motives, places, time, change and argument are the same words. What a novel does not give you is the specialised terms of a science passage, and those the exam usually glosses anyway.
Reading with a translation under each sentence lets you read at a level slightly above your own, which is where exam passages sit. You keep moving, the translation catches what you miss, and the words you meet repeatedly are the ones that turn up in the test.
Which books resemble exam texts
Essays are the closest thing to an academic passage: argument, evidence, an author's voice. Biographies and historical novels carry the vocabulary of dates, causes and institutions. Detective novels train the inference the questions ask for: who knew what, and when. Avoid dialect-heavy books and anything in verse until the exam is behind you.
Level matters. For B2 First, read the B2 shelf. For IELTS 7 and above and for C1 Advanced, the C1 shelf is the right difficulty, and its books are the ones whose sentences look like exam sentences.
Combining a word list with a book
Word lists exist for a reason: the Oxford 3000 and 5000 mark the words learners need by level, and the Academic Word List holds the 570 word families that academic texts use most. Their weakness is that a list gives you the word without its sentence. The fix is to use the list as a filter, not as a course: while reading, save the words that are on the list, with the sentence they came from, and let the ones not on the list go. In a month of reading you will have met most of the B2 list in context, which is how the exam expects you to know it.
A four-week plan
Week one: one short book at your target level, finished, with the audio on. Weeks two and three: a longer novel, 40,000 to 60,000 words, twenty minutes a day, saving list words as you meet them. Week four: read the saved words in the practice stories, then do two timed practice passages and notice how much less often you stop. The stopping is what the reading did.