[excellency]

Hey everyone,
I have a question about infinitives. There is a structure that says: an infinitive can be used as a noun, an adjective, or an adverb. I know about an infinitive that is used as a noun but my problem is with adjective and adverb.
For example:” to train is hard work.” Here to train is the subject and a noun.
But what about these ones? I have two examples for the adjective and the adverb.
She always has energy to spend. To spend is as an adjective.
He ran to win. To win is as an adverb.
Can anyone help me with these two examples? They are so strange to me. I have no understanding of them. Can you give me your own examples?

[susan53]

1. to train is hard work : This sounds odd to me. I would say Training is hard work. It is possible to use an infinitive as subject (this doesn't mean it's a noun, incidentally) - as in the expression To err is human. But it is less common in everyday speech than the gerund (the -ing form). One of the functions of this form is to nominalise a verb (ie to allow it to function grammatically in the sentence as a noun would) - as eg in I like reading or Using public transport causes less pollution than using your own car.. But that doesn't mean it "is" a noun.

2. She always has energy to spend : This structure is :
have (meaning possess) + object + to + infinitive. Other examples might be...
I have a lot of work to do today
He has three people to see before it's your turn.
We had about half an hour to wait before the train left

You could gloss them as
I have a lot of work which I must do...
He has three people who he must see..
We had about half an hour when we had to wait ..
She has a lot of energy which she has to/can spend

So in a sense the infinitive tells us something about the noun phrase - it defines it in some way. So it can be seen as having an adjectival function. But be careful - this doesn't mean it "is" an adjective.


3. He ran to win : You can think of this sentence as a "reduced" form of He ran in order to win In other words it's an infinitive of purpose, exactly the same as eg : I went to Rome to see John. The infinitive of purpose tells you why something happened - why he ran or why I went to Rome.

An infinitive of pupose is a non-finite, subordinate clause - and subordinate clauses do have an adverbial function. But be careful - it's an adverbial, not an adverb, and adverbial describes the function in the sentence, not the word class.


I think your confusion is because you're not distinguishing between grammatical word class (nouns, adjectives, adverbs etc) and syntactic function - how they are used in the sentence (nominally, adjectivally, adverbially etc). The two are quite different.

But does it matter? Do you need all this terminology for the exam you are working for? If not, just concentrate on the sentence patterns and their meanings and make sure you can use them to express what you want to say - whether you can recognise if the infinitive is being used nominally, adverbially or adjectivally is irrelevant to using it to communicate.

[susan53]

I've been thinking about no. 2 again, and of course it's not just "have" which can be followed by object + infinitive in this way - though I think it's very common with "have", which is probably why those examples came to mind first. but here are some other examples with different verbs. And it's the same thing happening - the infinitive could be glossed with a relative clause :


I couldn't think of anything to say (= which I could say)
He isn't the right person to ask (= who you should ask)
I need/want/would like something to help me sleep (= which will help me sleep)

Notice that the need/want/would like examples are not the "ordinary" use of the infinitive after these verbs - eg I need/want/would like David to be at the meeting. In this case, the to+infinitive clause couldn't be replaced by a relative clause - it's the equivalent of a that + SVC clause. And so the underlying structure is quite different.

[excellency]

thank a million susan53. your explanations were so useful and
the infinitives now are less confusing for me.

[lipard]

hi susan,...thanks for nice post about infinitives,..its very useful one ,..