根据人教新目标版九年级英语unit11《Could you please tell me where the restroom》完成下列句子,每空词数不限。 1. It is a very common and necessary activity to _____________. 2. Knowing _____________ is important. 3. We should change _____________we speak when talking with different people. 4. The expressions you use might depend on ___________ you are speaking to or __________ y ou know them. 5. 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.