As well-known author Mignon Fogarty says at the beginning of her Web article:
You may have heard there's a rule that you shouldn't split infinitives, but I'm here to tell you it's not a real rule, and the idea itself is based on a shaky foundation.In her Top Ten Grammar Myths, it's No. 2:
You shouldn't split infinitives. Wrong! Nearly all grammarians want to boldly tell you it's OK to split infinitives. An infinitive is a two-word form of a verb. An example is "to tell." In a split infinitive, another word separates the two parts of the verb. "To boldly tell" is a split infinitive because “boldly” separates “to” from “tell.”Mignon's article gives a lot of information about split infinitives, and I recommend reading it. Here's my brief advice in Garbl's Editorial Style Manual:
split infinitives Avoid awkward sentence constructions that split the infinitive forms of a verb, such as to leave or to help, as in this sentence: Try to not awkwardly or incorrectly split infinitives. But splitting infinitives is grammatically correct--and even useful if it helps strengthen the meaning of a sentence by placing the modifier before the word it's modifying: He wanted to really impress the council. Unfortunately, split infinitives can distract some readers who think they're incorrect.I list it first at Garbl's Myths and Superstitions of Writing, citing many writing authorities through the decades.
Mignon's article is featured today, Jan. 16, in my online daily paper, Garbl's Style: Write Choices, available at the Editorial Style tab above and by free email subscription.