A、Every ten minutes. B、Every other hour. C、Every hour. D、Every half hour. DHow often问的是频率。对话中，女士问前往市中心的公交车每隔多长时间一趟，男士说：“半小时一趟(Ev

W: Excuse me?
M: Yes, ma’am, can I help you?
W: Could you tell me where the bank is?
M: [6]It’s upstairs across from the coffee bar.
W: Thanks. Do you know what time it opens?
M: It should be open now. It opens at 8 a.m.
W: Good! And can you tell me how often the buses leave for the city center?
M: [7] Every half hour and you’ve just missed one.
W: Oh dear! Then I’ll have to wait for another thirty minutes. Thank you very much.
M: That’s OK.
6. Where is the bank?
7. How often do the buses leave for the city center?