dialogue: W: What's the matter with you? M: I've been having headaches. W: How long have they been bothering you? M: Umm... They started about two months ago. Oh, no. It must be about three months ago. At first, I thought as if I had flu because I had a running nose and a bit of a temperature. W: I see. And do the headaches come on at any particular time? M: They are usually worse in the morning, especially during the past two weeks. W: Now let me check if there is anything serious.
question: When did the problem begin?
choice: Two weeks ago. Two months ago. Three months ago.
answer: Three months ago.