How to use it
Project the game and click Open New Case. Students read the situation and argue their theory using modal verbs of deduction: must be, might be, can’t be for present situations and must have, might have, can’t have + past participle for past ones.
Use it as a whole-class warmer, or let pairs and small groups argue their own theories before comparing. The timer sets a discussion window, Detective’s Notes gives two or three model sentences per case, and the Evidence Locker is a quick reference for the target forms.