SOME USES OF THE INFINITIVE IN ENGLISH ( B2/ C1 LEVELS)

After studying the Gerund (-ING) in English, we should concentrate on the use of the INFINITIVE, as shown in the diagram above. The infinitive form of a verb is the verb in its basic form, with or without ‘to’. There are words (e.g adjectives, verbs, fixed expressions)  which make take: 

1. to infinitive;
2. bare infinitive;
3. to infinitive or bare infinitive.

Is it difficult? Not really. Let me make things easier for you, OK? 

Look at the diagram. Firstly, I have focused on the use of the 'bare infinitive', which is also known as infinitive without ‘to’. This infinitive structure commonly appears with the use of modal verbs.  Modals form a verb group, so they are used together with other verbs forming a verb group. Most grammars list the following verbs as modals: 'can', 'could', 'may', 'might', 'shall', ‘should', 'will', 'would', 'must' and 'ought (to)’. (Note that, if you regard ‘ought’ as a modal, it is followed by 'to infinitive'. )

Apart form modal verbs, there are other verbs followed by the 'bare infinitive'. Let’s take for instance ‘let’ and ‘make’ (e.g Do your parents let you stay up late? Why did you make her cry?). In turn, 'would rather' (=to talk about preferring one thing to another) and ‘had better' (=to talk about actions we think people should do) are also good examples of expressions which take the ‘infinitive without to'. ( e.g I’d rather do something else/  It’s late. I’d better go now.)

The ‘to infinitive' is commonly used to express purpose. This meaning may also be conveyed by the expressions “so as to" and  “in order to”. (e.g When I travel, I check my suitcase twice ( in order) to make sure I have packed everything I will need). The 'infinitive with to' is also used after some adjectives, transitive verbs and fixed expressions. Note how necessary it is to complete the meaning of these words. Just ask the questions 'Who?  what? what for?'. The fixed expression 'Be able to’, expresses ‘ability’ ( e.g He’s able to speak several languages). As for 'be bound to’, it means that something is certain to happen in the future ( e.g John is bound to get that job).

Finally, pay attention to some verbs which can be followed by either the 'to infinitive' or  the 'bare infinitive'. In English, we can both say 'help someone to do something or help someone do something." 

Other verbs which deserve our attention are ‘dare’ and ‘need’. 

In British English, these verbs can be followed by the 'bare infinitive' only in negative sentences and in questions. Have a look at these examples taken both form the Collins Cobuild English Grammmar and the Online Cambridge Dictionary (dictionary.cambridge.org/pt/dicionario/ingles/dare)

How dare you speak to me like that? ( bare infinitive in questions)

Need you go home so soon?  ( bare infinitive in questions)

He needs to lose some weight. ( to infinitive in affirmative sentences)

I don't think we need ask him.(bare infinitive in negative sentences)

 For Portuguese Speakers. 

O uso do -ING, quando não expressa -ando, -endo e -indo, bem como o uso do infinitivo em inglês, normalmente geram dificuldade para os brasileiros.  Os alunos cometem erros pois não percebem que há tanto o ‘to infinitive’ quanto o “bare infinitive’. Notem que se em português dizemos: ‘Ele me fez chorar’, o equivalente em inglês é “He made me cry, e não “He made me to cry. Além disso, é bastante comum ocorrer o erro quando o verbo requer o -ING, mas em português usa-se o infinitivo. (e.g .Would you mind closing the door to me?/ Você se importaria de fechar a porta para mim).

Gostaria também de chamar atenção para o verbo ‘want’. Em português dizemos ‘Eu quero que você venha à minha festa’. Entretanto, em inglês, a estrutura verbal é bem diferente, pois precisamos do 'to infinitive’- e. g 'I want you to come to my party’. ( want + someone+ to do something)