Given the peculiarities of the grammatical class represented by verbs, the infinitive constitutes one of its nominal forms. Such a statement is plausible, however it needs some additions – which is why this article lends itself.
In this sense, we will observe some characteristics related to the nominal form in question. Look:
* The infinitive presents a verbal process free from the notion of tense or mood. Thus acting as a form used to name verbs. Let's look at some examples:
Sing it's a good exercise for the soul.
Practice sports are good for your health.
To sleep well brings health benefits.
* This same form can also become a noun, with the presence of an element that acts as a determinant (the article, for example). Let's stick to the following example:
O sing of birds resembles a symphony.
We found that from a verb to a noun (singing).
* In Portuguese, the infinitive can be personal, that is, related to some being; and impersonal, not restricted to any specific being. Let's look at the examples below:
take care of personal image is necessary. (referring to the first person plural – us)
To respect the next represents a virtue. (not restricted to any being)
* In the condition of compound form, the infinitive has a past value, referring to a process already completed at the time of speaking or writing. Let us analyze the cases elucidated below:
have trusted in you opened horizons for my personal growth.
have run well the function, granted me a position of trust.
By Vânia Duarte Graduated in Letters.
Source: Brazil School - https://brasilescola.uol.com.br/gramatica/caracteristicas-infinitivo.htm