库赛湖位于藏北高原，库赛河是其接纳的最主要的地表径流。冬季湖面结冰，冰上多布有风沙活动带来的砂砾。湖床沉积物中发育有粗细颗粒相间分布的连续、规则纹层。研究发现，细颗粒层具有流水搬运沉积特征，而粗颗粒层不具此特征。下图为库赛湖地形及取样点沉积层垂直剖面示意图。据此完成下列各题。

A: You must be really excited about leaving for London tomorrow, Judy!

B: Yeah.____

A: Nervous about what?

B : I don't know many of the customs and manners in UK.____

A : Sure.

B:____

A: Well, it's important to be on time when you're invited for dinner.

____ The British expect their guests to be on time.

B: Then how long may I stay there?

A:____ Or you seem to have come only for the meal. When your friends seem to be getting sleepy and running out of things, it's time to leave. The next day, call or write a thank-you note to say how much you enjoyed the evening.