This document discusses how question words like when, where, how, who, whom, whose, what, which and whether can be followed by an infinitive. It provides examples of sentences with question words followed by should or can/could expressed as an infinitive, and how they have the same meaning as sentences using question words followed directly by should or can/could. The document aims to illustrate how infinitives can be used after question words to express should or can/could without changing the overall meaning.