Question

A split infinitive is an infinitive that
a. is used without the word "to."
b. has a word between "to" and the verb.
c. must have a subject.
d. is used as an adjective or a noun.

Answer 1

A split infintive is an infintive that b. has a word between "to" and the verb. (Why do you think they call it split?)

Examples: 
to boldly go where no man has ever gone before
she seems to really like it

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