“To ‘ing’ or not to ‘ing’ – that is the question?” by Petra Keyser is a concise practice booklet that helps learners confidently choose between the Simple Present and the “-ing” form (Present Progressive/Continuous). It includes clear grammar reminders (formation, signal words, question/negation rules and modals), varied exercises, a short reading text with error-spotting, and a “tricky” section on cases where -ing is (not) possible. Complete solutions/answer keys are provided, making it ideal for self-study, revision or classroom use.