根据课文内容，完成下列任务。 A. 完成下列表格,每空词数不限. How to ask politely BAD GOOD Where are the potato chips? Could you please tell me (1)__________? There's no milk left, is there? Excuse me. Do you know (2)____________? How does this work? Can you show me (3)_____________? Give me a pound of that. (4)_____________, please? B. 完成下列句子,每空词数不限. 5. It is a very common and necessary activity to _____________. 6. Knowing _____________ is important. 7. We should change _____________we speak when talking with different people. 84. The expressions you use might depend on ___________ you are speaking to or __________ you know them. 9. If you stop a stranger in the street, we might first say 'Excuse me. __________' or 'I'm sorry to trouble you but,' before asking them for help.