Skip to content
Mastery / B2 First

LC5.2 · Infinitives, Gerunds & Participles · B2 First

Gerunds as subjects/objects in B2 First

In everyday speech, learners default to infinitives everywhere: "enjoy to swim", "interested in to learn". But English has strict rules: "stop smoking" and "stop to smoke" mean opposite things. Some verbs only accept -ing (enjoy, avoid, consider), others only accept infinitive (want, decide, hope), and a treacherous group accepts both with different meanings (remember, try, stop). Cambridge uses them in Part 4 to test whether you can distinguish the nuance.

Competency 21 of 82 Appears mainly in Part 4 — Key Word Transformation

Where it appears in the exam

Dónde aparece esta competencia en el B2 First Frecuencia con la que esta competencia aparece en cada parte del examen B2 First. B2 First Reading & Use of English Part 1 Multiple Choice Cloze Raro Part 2 Open Cloze Raro Part 3 Word Formation Part 4 Key Word Transformation Ocasional Part 5 Multiple Choice Contextual Part 6 Gapped Text Contextual Part 7 Multiple Matching Contextual Frecuente Ocasional Raro Contextual No aplica

What is it?

The gerund (-ing as a noun) functions as a subject ('Swimming is fun'), as the object of certain verbs ('I enjoy swimming') and as an obligatory complement after prepositions ('good at swimming'). At B2 level, the challenge is not the -ing form itself, but the system of verb patterns: which verbs demand a gerund (enjoy, avoid, consider), which demand an infinitive (want, decide, hope), and which accept both with DIFFERENT meanings (stop, remember, try, forget, regret). This last group is Cambridge's favourite weapon.

Why it matters in the exam

Part 4 (Key Word Transformation) exploits dual-pattern verbs: transform 'I will never forget meeting her' into 'I will always remember meeting her' (both gerund = past) or 'Don't forget to call' into 'Remember to call' (both infinitive = future). Also expressions with prepositions: 'no point in + -ing', 'succeed in + -ing', 'insist on + -ing'. Part 2 can ask for the preposition preceding the gerund ('interested ___ learning' → 'in'). In Writing, gerunds as subjects allow you to open paragraphs with sophistication: 'Working from home has transformed the way people live' — high register, Language points.

The cognitive trap

Instinct

"The instinct: "I avoid to eat sugar" / "interested in to learn" / "stop to smoke" (meaning quit)"

Why your brain does this: in most languages, the infinitive is the default form after verbs and prepositions. Your brain has no category for 'gerund as noun' — it instinctively reaches for the infinitive every time.

Rule

"I avoid eating sugar." / "interested in learning" / "stop smoking" ≠ "stop to smoke"

The English rule: the gerund (-ing) functions as a noun. After 'enjoy', 'avoid', 'consider', English requires -ing, not infinitive. Your instinct produces 'avoid to eat' — incorrect. Worse: after EVERY preposition, English requires -ing ('interested in learning', 'good at cooking'). The pattern 'interested in to learn' is one of the most common errors learners make.

Recognition pattern

Gerund (-ing) or infinitive (to + verb)?
Does the verb come AFTER a preposition? (in, on, at, of, about, for, without)
GERUND obligatory: 'interested in learning', 'good at cooking', 'tired of waiting'
NO
Does the verb function as the SUBJECT of the sentence?
GERUND as subject: 'Swimming is healthy', 'Learning languages takes time'
NO
Is the main verb enjoy, avoid, consider, suggest, mind, deny, risk, practise, imagine, admit, finish, keep, miss?
GERUND obligatory: 'enjoy reading', 'avoid making mistakes'
NO

In the exam, look for the key signal first. The answer follows.

Recognition signals in the text

Signal Form
preposition + ___ (gap after in, on, at, of, about, for, without) Gerund (-ing) — after a preposition ALWAYS -ing

"She's interested in ___ a new career." → 'starting' (NOT 'to start')

Signal Form
___ + is/are/was (gap at start of sentence, before copular verb) Gerund as subject

"___ regularly is important for your health." → 'Exercising'

Signal Form
enjoy / avoid / consider / suggest / mind / risk + ___ Gerund obligatory

"I don't mind ___ early if necessary." → 'getting up'

Signal Form
remember / forget + ___ (action PAST or FUTURE?) Past = -ing ('remember doing'). Future = to ('remember to do')

"I remember ___ my first bike." → 'riding' (past recall)

Signal Form
stop + ___ (QUIT doing or PAUSE TO do?) Quit = -ing ('stop doing'). Pause to = to ('stop to do')

"She stopped ___ sweets." → 'eating' (quit eating)

Signal Form
there's no point in / it's worth / it's no use / can't help + ___ Gerund obligatory — fixed expressions with -ing

"There's no point in ___ ." → 'worrying'

Signal Form
succeed in / insist on / apologize for / look forward to + ___ Gerund obligatory — verb + fixed preposition + -ing

"I look forward to ___ from you." → 'hearing'

The mistakes Cambridge exploits

Wrong

"I enjoy to read before bed."

Direct transfer from most languages where verbs take infinitives. Your brain produces infinitive because it's the natural form after verbs in most language systems. In English, 'enjoy' + infinitive is grammatically impossible.

Right

"I enjoy reading before bed."

'Enjoy' demands a gerund. No exceptions, no alternative.

Wrong

"She's interested in to learn Japanese."

A very common error among exam candidates. In most languages, 'interested in to learn' uses an infinitive. In English, 'in' is a preposition → demands -ing. 'To learn' after a preposition doesn't exist.

Right

"She's interested in learning Japanese."

After a preposition ('in'), ALWAYS gerund. 'In' demands -ing as its complement.

Wrong

"I can't help to laugh when I see that video."

'Can't help' is a fixed expression that ALWAYS takes a gerund. 'Can't help to laugh' doesn't exist — the correct pattern is 'can't help + -ing'. Same as 'it's no use', 'it's worth', 'can't stand'.

Right

"I can't help laughing when I see that video."

'Can't help' is followed by -ing (gerund), never by to + infinitive. 'Can't help laughing' = I can't stop myself from laughing.

Wrong

"I stopped to smoke last year." (if you mean 'I gave up smoking')

'Stop + to' means the opposite: 'I paused IN ORDER TO smoke' (you stopped another activity to have a cigarette). Choosing the wrong form reverses the meaning. For 'give up the habit' → 'stop smoking', not 'stop to smoke'.

Right

"I stopped smoking last year." (= I gave up the habit)

'Stop + -ing' = give up an activity. For 'I quit smoking' (gave up the habit), the obligatory form is the gerund.

Wrong

"I look forward to hear from you."

Classic trap: 'to' looks like an infinitive marker, but in 'look forward to' it is a PREPOSITION. Test: if you can substitute with a noun ('I look forward to THE MEETING'), it's a preposition → -ing.

Right

"I look forward to hearing from you."

'Look forward to' — this 'to' is a PREPOSITION, not an infinitive marker. It demands -ing.

Why your brain gets it wrong

The learner's short circuit

Analyse the trap by exam format

Part 4 — Key Word Transformation

I'll never forget the day I met my best friend at university. I'll always ______ my best friend at university. (REMEMBER)

Your brain
You wrote remember to meet
Correct remember meeting

Your brain sees 'remember' and defaults to infinitive ('remember to meet'). But the sentence describes a PAST memory — something that ALREADY happened. 'Remember + -ing' = recall something you did. 'Remember + to' = not forget to do something future. Here the meeting already took place.

The signal

the day I met / REMEMBER

'I'll never forget the day I MET' → past. 'Remember' + past event = remember + -ing. If the action already happened, the gerund is obligatory.

remember meeting

The TIMING of the action decides the form

With 'remember', 'forget' and 'regret', ask yourself: did the action already happen or is it yet to come? Past = -ing. Future = to. Cambridge builds sentences where the temporal context is the ONLY clue.

Strategy

Step 1: Has the action following 'remember/forget' already HAPPENED? → -ing ('I remember meeting her'). Step 2: Is the action still TO DO? → to ('Remember to call me'). The time of the subordinate action, not the main clause, decides.

Gerunds as subjects/objects is 1 of 82

The exam tests 82 grammar competencies across 19 families. Mastering one is the first step. Automating all 82 is passing.

Tiempos verbales 6
Modales 5
Pasiva y causativa 2
Condicionales 6
Infinitivo, gerundio y participio 5
Énfasis y orden de palabras 4
Oraciones de relativo 4
Reported Speech 4
Comparativos y superlativos 5
Conectores 5
Preposiciones 4
Colocaciones y phrasal verbs 4
Formación de palabras 6
Determinantes y cuantificadores 4
Adjetivos y adverbios 5
Preguntas y negación 4
Patrones verbales 3
Concordancia y ortografía 3
Vocabulario 3

Keep practising

Now you understand how it works in the exam. Automating it requires guided practice.

Start your preparation

Free. No credit card.

Start your preparation →