B: I can’t think of it off the top of my head. Maybe we can look it up in our notebook, but I don’t have mine with me.
A: That’s too bas! I don’t have it with me, either. Do you remember the number of the lecture hail?
B: Sorry, I can’t think of it off my head.
A: I’m terribly interested in the lecture. I can’t miss it!
B: Well, why don’t you call the dean who arranged the lecture?
A: I’m afraid it’s not very wise to ask the dean directly.
B: Then maybe you can call the office if the department and ask the secretary.
A: I’ve already tried, but no one answered.
B: Oh!
A: You usually have a powerful memory, but you can’t help today. You memory seems to be fading early.
B: It’s nit that my memory is fading. I do have a good memory for faces and names, but a poor one for numbers and dates.