Английского

particle analogous, mutatis mutandis, to other auxiliary elements in 
the English grammatical structure. Its only function is to build up 
and identify the infinitive form as such. As is the case with the 
other analytical markers, the particle to can be used in an isolated 
position to represent the whole corresponding construction syn-
tagmatically zeroed in the text. Cf.: You are welcome to acquaint 
yourself with any of the documents if you want to. 
Like other analytical markers, it can also be separated from its no-
tional, i.e. infinitive part by a word or a phrase, usually of adverbial 
nature, forming the so-called "split infinitive". Cf.: My task is not 
to accuse or acquit; my task it to thoroughly investigate, to clearly 
define, and to consistently systematise the facts. 
Thus, the marked infinitive presents just another case of an analyti-
cal grammatical form. The use or non-use of the infinitive marker 
depends on the verbal environment of the infinitive. Namely, the 
unmarked infinitive is used, besides the various analytical forms, 
with modal verbs (except the modals ought and used), with verbs 
of physical perceptions, with the verbs let, bid, make, help (with 
the latter — optionally), with the verb know in the sense of "ex-
perience", with a few verbal phrases of modal nature (had better, 
would rather, would have, etc.), with the relative-inducive why. All 
these uses are detailed in practical grammar books. 

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The infinitive is a categorially changeable form. It distinguishes the 
three grammatical categories sharing them with the finite verb, 
namely, the aspective category of development (continuous in op-
position), the aspective category of retrospective coordination (per-
fect in opposition), the category of voice (passive in opposition). 
Consequently, the categorial paradigm of the infinitive of the ob-
jective verb includes eight forms: the indefinite active, the continu-
ous active, the perfect active, the perfect continuous active; the in-
definite passive, the continuous passive, the perfect passive, the 
perfect continuous passive. E.g.: to take — to be taking 
— 
to have taken — to have been taking; to be taken —to be 
being taken — to have been taken — to have been being taken. 
The infinitive paradigm of the non-objective verb, correspond-
ingly, includes four forms. E.g.: to go —to be going 
— 
to have gone — to have been going. 
The continuous and perfect continuous passive can only be used 
occasionally, with a strong stylistic colouring. But they underlie 
the corresponding finite verb forms. It is the indefinite infinitive 
that constitues the head-form of the verbal paradigm.