📏 Grammar B1-14: Obligation: consolidation

A2 taught must, have to and should as separate topics; this material welds them into one system with two axes — how strong the pressure is (must / have to, then should, then can) and which direction it pushes (obliged, advised, free, forbidden). The two load-bearing contrasts each get a compared pair with a verdict: mustn’t bans the action while don’t have to only removes the duty, and must announces the speaker’s own rule while have to reports an outside one. The genuinely new B1 ground is time: must and mustn’t have no past or future, so had to and will have to take over — a takeover with its own formula, two worked runs (including the past ban, which needs couldn’t or wasn’t allowed to) and dedicated practice. need to and don’t need to appear throughout as the everyday twins of have to and don’t have to. The context text is Livia’s first Saturday job at a garden centre, mixing every strength in one dialogue with tap-to-explain reasoning. Practice is heavy: thirty-eight multiple-choice items across five sets, a ten-chip sorter on the rule-maker, six repairs and three trap boxes, every answer teaching a reason. Teacher notes add a 45-minute sequence, a two-axis board move and the Cambridge B1 Preliminary connection.