This is an example of an adverb being transferred into split infinitive position from a parallel position in a different construction. Transformational grammar Transformational grammarians have attributed the construction to a re-analysis of the role of to. Types In the modern language, splitting usually involves a single adverb coming between the verb and its marker. Very frequently, this is an emphatic adverb, for example: I need you all to really pull your weight. I'm gonna (=going to) totally pulverise him. Sometimes it is a negation, as in the self-referential joke: Writers should learn to not split infinitives. However, in modern colloquial English, almost any adverb may be found in this syntactic position, especially when the adverb and the verb form a close syntactic unit (really-pull, not-split). Compound split infinitives, i.e., infinitives split by more than one word, usually involve a pair of adverbs or a multi-word adverbial: We are determined to completely and utterly eradicate the disease. He is thought to almost never have made such a gesture before. This is a great opportunity to once again communicate our basic message. Examples of non-adverbial elements participating in the split-infinitive construction seem rarer in Modern English than in Middle English. The pronoun all commonly appears in this position: It was their nature to all hurt one another. and may even be combined with an adverb: I need you to all really pull your weight. However an object pronoun, as in the Layamon example above, would be unusual in modern English, perhaps because this might cause a listener to misunderstand the to as a preposition: *And he called to him all his wise knights to him advise. While, structurally, acceptable as poetic formulation, this would result in a garden path sentence particularly evident if the indirect object is omitted: Other parts of speech would be very unusual in this position. However, in verse, poetic inversion for the sake of meter or of bringing a rhyme word to the end of a line often results in abnormal syntax, as with Shakespeare's split infinitive (to pitied be, cited above), in fact an inverted passive construction in which the infinitive is split by a past participle. Presumably, this would not have occurred in a prose text by the same author. Finally, there is a construction with a word or words between to and an infinitive that nevertheless is not considered a split infinitive, namely, infinitives