Gerunds and Infinitives – an approach

There are certain areas of English grammar that never fail to make students throw up their hands in horror and sigh deeply at the impossibility of ever mastering them. Some years ago, while teaching a group for the Cambridge Certificate of Proficiency in English, I found myself answering endless question on when to use a gerund and when to use an infinitive. It was easy to answer the individual questions, but I wanted to give my students more. I wanted to give them a method they could use in order to work out for themselves when to us a gerund and when to use an infinitive.


The first thing to stress is that English speakers do not find this difficult. This may seem obvious, but there are areas of English grammar that native speakers have trouble with. The third conditional springs to mind. So, I decided I needed to look at the nature of gerunds and infinitives and to define what made them different from each other.

Potentiality versus actuality

This is the essence of the difference. Gerunds are used for things which ‘are’ or ‘were’ (actuality) and infinitives are used for things which may be (potential) but are not ‘actual’ at the moment of speaking. That is why the verb ‘want’ is followed by an infinitive and ‘finish’ by a gerund. You finish something that you have started, so it is ‘actual’ you want to do something before you do it, so it is potential at the moment of speaking.

Some verbs can be followed by either a gerund or an infinitive. You might say: ‘I need to have a haircut’ or ‘My hair needs cutting’. In the first instance, you are talking about something you need to do in the future (potential); in the second you are talking about the situation of your hair at the moment of speaking (actual).

In general, verbs talking about things which are, or are not, to come take the infinitive: expect, arrange, enable, forbid, encourage, persuade, force, order, remind, wish, etc. Verbs which are about things in progress or finished take the gerund: deny, avoid, resent, enjoy, resist, mention, admit, continue, fancy, etc.

Of course, I hear you shout, there are also verbs which look like they should go into one category but go in the other. ‘Suggest’ is a case in point. We use the gerund with ‘suggest’, although it appears to be talking about the future. In fact, there are two ways to use the verb. You can say: ‘I suggest you go to the doctor’ where the meaning is closer to that of an infinitive (although technically, this is not an infinitive) and there is a certain amount of distance implied. Equally, you can say: ‘I suggest going to the cinema tonight’ where the action is clearly in the future but the use of the gerund makes the activity more ‘real’. This is because the use of ‘suggest’ makes the thing suggested as real as possible and that can only happen if you use the gerund. The suggestion is made at the moment of speaking and it is actual at that point.

There are other verbs where the use of the gerund or the infinitive can change the meaning. Two of the most commonly used are ‘remember’ and ‘forget’. If you remember to do something, the action you do is potential at the moment of speaking; if you remember doing something, the action you remember is obviously in the past. Similarly, if you forget to do something, the action remains potential but it is never actually done; if you forget doing/having done something, the assumption is that the action took place but you cannot remember it.