----- Nội dung ảnh ----- 1. Hello. Could / Can I speak to Mrs Johnson, please? 2. We could / were allowed to go home early yesterday because our teacher was ill. 3. The head teacher said we could / were allowed to go home. 4. Do you think I should / could be worried about these spots on my forehead? 5. You ought to / should enter that talent contest! 6. You couldn't / shouldn't talk to people like that! It's rude!