Part 4 of the C1 Advanced Reading and Use of English paper gives you six pairs of sentences. The first is complete. The second has a gap, and a key word is supplied. You fill the gap so the second sentence means the same as the first. Strict word rules decide whether a correct idea earns marks.

This guide covers those rules, the two-part mark scheme, a six-step method and five practice items from the ScoreFluent bank with answer keys and reasons. The other Use of English parts are open cloze and word formation.

What are key word transformations in C1 Advanced?

Part 4 has six questions. Each has three elements: a lead-in sentence, a key word, and a second sentence of which only the beginning and end are given. You fill the gap so that the second sentence is similar in meaning to the lead-in. The gap needs between three and six words, one of which must be the key word, and the key word must not be changed in any way (C1 Advanced Handbook for Teachers; Cambridge exam format).

The handbook says Part 4 tests vocabulary and grammar together, and that a range of structures is tested.

Checked 15 and 16 October 2026 against the sources linked above. ScoreFluent is not affiliated with Cambridge University Press & Assessment.

How are key word transformations marked?

Each question is worth up to two marks. The mark scheme splits an answer into two parts and gives one mark for each part that is correct (handbook). A wrong answer or no answer scores zero, and there is no negative marking (information for candidates). Part 4 feeds the Use of English score, which Cambridge bases on Parts 2, 3 and 4 (same source).

The split matters. If the answer is so as not to wake, the two parts could be so as and not to wake. You can earn one mark for knowing the purpose structure even if you slip on the second half. Our practice keys below show the split for each item, in the same two-part way.

What are the word-count rules?

  • Three to six words, including the key word. The handbook says your answer must not exceed six.
  • The key word stays exactly as given. Do not add an ending or change its tense.
  • Contractions count as two words. The candidate guide says to use the full form to count, so didn't is did not, which is two words. The handbook also says contracted forms are not acceptable answers and only full forms should be used. Write the full form and you avoid the question.
  • Spell every word correctly. American spelling is accepted if you do not mix varieties.

How do I approach a key word transformation?

  1. Read the lead-in for its meaning, not its words. Decide what must stay the same: who does what, when, and whether it is positive or negative.
  2. Ask what structure the key word forces. WISH points to wish plus a subject plus would. ONLY at the start points to an inversion. BEEN in a gap that starts the sentence points to had it not been.
  3. Write the gap with the key word unchanged. Say the whole second sentence aloud.
  4. Count the words. Three to six, contractions as two. If you have seven, find a shorter structure.
  5. Check meaning, tense and spelling. Is the time reference still right? Is a negative still a negative?
  6. If you can only get half, write half. The marks are per part.

Which structures show up in our practice items?

Cambridge says a range of structures is tested. It does not publish a list, and this page does not claim how often each appears. The five practice items below show:

  • Purpose. So as not to wake.
  • Reporting verbs. Promised to call me.
  • Wishes about habits. Wish Tom would stop.
  • Inversion after a negative adverb. Not only does the bakery sell.
  • Inverted third conditional. Had it not been.

What mistakes lose marks in Part 4?

  • Changing the key word. Wished where WISH is given breaks the rule.
  • Going over six words. Check before you move on, especially when contractions are involved.
  • Matching the grammar but not the meaning. Not only the bakery sells has the right key word and the wrong grammar. After not only at the start of a clause you need the auxiliary before the subject.
  • Missing the backshift. In "Rita …… the next day", the answer needs a past form (promised to call me), not will call me.

How should I practise Part 4?

Sort structures into families (passives, reporting, wishes, conditionals, inversions, fixed phrases). For each miss, write the structure the key word forced, the full correct second sentence, and one of your own sentences using it. Review the log in three days.

Where can I try C1 Advanced key word transformation practice items?

Practice items from the ScoreFluent bank (not real exam questions)

Complete each gap in three to six words, including the key word. Then open the key. The gap is shown as dots.

  1. He spoke quietly in order not to wake the baby.
    Key word: AS
    He spoke quietly …… the baby.
  2. 'I'll call you tomorrow,' Rita told me.
    Key word: PROMISED
    Rita …… the next day.
  3. I'd like Tom to stop interrupting me.
    Key word: WISH
    I …… interrupting me.
  4. The bakery sells bread and also trains local apprentices.
    Key word: ONLY
    …… bread, it also trains local apprentices.
  5. If the lifeguard had not reacted so swiftly, the boy would have drowned.
    Key word: BEEN
    …… for the lifeguard's swift reaction, the boy would have drowned.
Answer key, mark split and why
  1. so as not to wake / so as to avoid waking. Two marks, one per part: [so as] + [not to wake / to avoid waking]. So as (not) to + infinitive expresses purpose.
  2. promised to call me / promised she would call me / promised to phone me / promised to ring me. Two marks, one per part: [promised to / promised she would] + [call me / phone me / ring me]. Promise takes a to-infinitive or a that-clause with would.
  3. wish Tom would stop. Two marks, one per part: [wish Tom] + [would stop]. Wish + subject + would expresses annoyance at a present habit.
  4. Not only does the bakery sell / Not only does it sell. Two marks, one per part: [Not only] + [does the bakery sell / does it sell]. Not only at the start of a clause is followed by auxiliary + subject inversion.
  5. Had it not been / If it had not been / If it hadn't been. Two marks, one per part: [Had it not / If it had not / If it hadn't] + [been]. Had it not been for / if it had not been for + noun phrase introduces a third-conditional condition.

How does ScoreFluent practise this part?

The C1 Advanced Reading and Use of English sectional mock test and the full mock test include this task. Results are practice estimates, not official Cambridge scores. New accounts get 40 free credits and credits never expire. There is no subscription, and reading practice is free within a daily limit (pricing). Start with 40 free credits →

Where next: the C1 Advanced hub, the Reading and Use of English guide, the multiple-choice cloze guide and the full list of C1 task guides.

Where did these facts come from?

Checked 15 and 16 October 2026. ScoreFluent is not affiliated with or endorsed by Cambridge University Press & Assessment. The practice items above come from ScoreFluent's own bank and are not real exam questions.

Questions students ask

How many words can I write in a C1 Advanced key word transformation?

Between three and six, and one of them must be the key word. The key word must not be changed in any way.

How many marks is each key word transformation worth?

Up to two. Cambridge splits each answer into two parts and gives one mark for each part that is correct, so a half-right answer can still earn a mark.

How many questions are in C1 Advanced Part 4?

Six. Each has a lead-in sentence, a key word and a second sentence with a gap, and the finished second sentence must be similar in meaning to the first.

Do contractions count as one word or two in Part 4?

Two. Cambridge's candidate guide says to count the full form, so didn't is did not, which is two words. The handbook also says to use full forms, so writing them out is the safest choice.

Can I change the form of the key word?

No. Cambridge says the key word must not be changed in any way, so writing wished for the key word WISH, for example, is wrong.

Does Part 4 count towards the Reading or Use of English score?

Use of English. Cambridge bases that score on Parts 2, 3 and 4.

What does Part 4 test?

Both vocabulary and grammar, across a range of structures. Cambridge says the ability to express a message in a different way shows flexibility and resource in the use of language.

Should I leave a gap blank if I only know half the answer?

No. Because the mark scheme gives one mark per part, write the part you are sure of. There is no negative marking.

How do I get better at key word transformations?

Group structures in families, such as passives, reporting verbs, wishes, conditionals and inversions, and practise turning one into another. For each miss, write the structure the key word forced and the full correct sentence.

Are the practice items on this page real C1 Advanced questions?

No. They are ScoreFluent practice items, and ScoreFluent is not affiliated with Cambridge University Press & Assessment. Practice results are estimates, not official Cambridge scores.

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