English Gerunds vs Infinitives

A gerund is the -ing form of a verb used as a noun: Swimming is good exercise. Reading books improves vocabulary. An infinitive is to + the base form of a verb, often used to express purpose, intention, or outcome: I want to swim. She decided to read more. Both can follow verbs, but each verb has its own pattern. Some verbs take only gerunds (enjoy, avoid, finish), some take only infinitives (want, decide, promise), and some take both with or without a change in meaning.

Stop doing means to cease an activity permanently or for now: She stopped smoking (she no longer smokes). The gerund is the object of the verb stop — the thing being stopped. Stop to do means to pause what you are currently doing in order to do something else: She stopped to check her phone (she paused and then checked). The infinitive here expresses purpose. This distinction is important and commonly tested in B2 exams.

The correct form is I look forward to hearing. The word to in this phrase is a preposition, not part of an infinitive construction, and prepositions must be followed by a gerund (-ing form), not a bare infinitive. Other similar expressions: be used to doing, be accustomed to doing, object to doing, be committed to doing, get around to doing. A common error is treating to as the infinitive marker and writing look forward to hear, which is incorrect.

The most important pairs: remember doing (recall a past event) vs remember to do (not forget a future task); forget doing (have a memory of) vs forget to do (fail to do); stop doing (cease an activity) vs stop to do (pause in order to do); try doing (experiment) vs try to do (make an effort); regret doing (feel sorry about a past action) vs regret to do (formal, sorry to say); go on doing (continue) vs go on to do (move to the next stage).

They can take both forms with little difference in meaning: I like swimming / I like to swim. However, there is a subtle distinction: the gerund often implies a general enjoyment or habitual activity, while the infinitive can imply a specific choice or occasion. With would like, would love, would hate, would prefer, the infinitive is standard: I would like to go. Would like doing is not used. In American English, the infinitive is more common after like; in British English, both are equally common.

Common verbs that must be followed by a gerund: enjoy, avoid, finish, keep, miss, mind, consider, imagine, suggest, admit, deny, practise, recommend, risk, involve, resist, postpone, delay, give up, can't help, can't stand, it's no use, it's worth, there's no point. A useful tip: verbs related to completion, avoidance, or habitual activity tend to take gerunds. Learning these in topic groups rather than random lists makes them easier to remember.

Common verbs requiring a to-infinitive: want, need, wish, decide, plan, hope, expect, intend, arrange, manage, aim, promise, refuse, agree, offer, threaten, attempt, learn, afford, choose, tend, seem, appear, fail, pretend, demand, deserve. Verbs related to future intentions, promises, decisions, and attempts tend to take infinitives. Some of these can also take an object before the infinitive: ask someone to do, tell someone to do, want someone to do.

Make and let are followed by an object and a bare infinitive (infinitive without to): She made me wait. He let her leave early. These are causative verbs. Compare: She made me wait (bare infinitive, no to) vs She asked me to wait (full infinitive with to). In the passive, make takes the full infinitive: I was made to wait. Let does not have a common passive form. Help can take either a bare or full infinitive: She helped me (to) understand.

In Cambridge B2 First Use of English Part 1 (multiple choice cloze) and Part 2 (open cloze), you may need to choose or supply the correct verb form. In Part 4 (key word transformation), you are often required to rewrite a sentence using a given word, which may involve switching between a gerund and infinitive pattern: She didn't remember that she had locked the door → She didn't remember locking the door. Knowing the meaning-changing pairs (stop, remember, forget, try, regret, go on) is essential for this section.

Yes. A gerund can function as the subject of a sentence: Swimming every day keeps you healthy. Reading before bed helps you sleep. Arguing about it is pointless. In formal written English, gerunds as subjects are more common than infinitive subjects (To argue about it is pointless is grammatically correct but sounds very formal). Gerunds as subjects are treated as singular and take a singular verb: Running marathons is a serious commitment (not are).