split infinitive

The split infinitive is a stylistic issue that has been rationalized into a grammatical one. There is no grammatical basis for rejecting split infinitives, since to regard an infinitive with to as an inseparable unit has no support in the typical structures of English grammar, which freely separates particles, auxiliary verbs, and other qualifiers from the words to which they belong (e.g., in I have never been to Paris the word never separates have from been). The issue is one of style and not of grammar. If splitting an infinitive produces awkwardness, it is better to avoid it, but if the split is natural and supports or clarifies the meaning, there can be no objection to it. The adverb belongs closely with the verb in the infinitive in cases such as They agreed to flatly forbid such actions and They were plotting to secretly copy the files, but can be moved to a more comfortable position in other cases such as We expect to further modernize our services (revise as: ... to modernize our services further) and I would like to briefly mention a few points (revise as: I would like briefly to ...). It is usually advisable to avoid splitting the infinitive with an adverbial phrase (e.g., They were trying to in some way improve the situation). In some cases, however, even an adverbial phrase cannot be separated from its verb: Prices are likely to more than double (in which more than double is effectively regarded as a set verb phrase). The guiding principle, in sum, is that the split infinitive is acceptable when the rhythm and meaning of the sentence call for it or when its use is that of a set verb phrase. It should be avoided (either by repositioning or by rephrasing) when it seems stilted or awkward, or creates ambiguity, especially in formal writing where its inclusion may draw criticism.