... * MODAL in the PASSIVE: MODALS dạng bị động S + modal + V + O S + modal + Be + V3/ ed + By + O Example : Humans must keep water, air, and land clean Water, air, and land must be kept clean ... cinema - If I were you, I would stay at home * NOTES: Khi ta mà ta nói việc Quá Khứ, cách sử dụng MODALS có dạng: S + MODAL + HAVE + P2/ED should, must ,needn’t 1/ SHOULD + HAVE + P2/ED (lẽ nên…) ... needn't water b needn't be watered c needn't be watering d needn't have watered 17 People _ hunt and use whales for commercial purpose A needn’t B mustn’t C don’t need to D don’t have to 18 She...