answer: #Person2#'s car is broken. #Person1# and #Person2# are looking for the reasons.
documents: #Person1#: Dear, can you drive me to the clinic? 
  #Person2#: I'm afraid I can't. 
  #Person1#: Why? 
  #Person2#: Well, my car won't start. I don't know what's the matter with it. 
  #Person1#: Could it be the battery? 
  #Person2#: No, I don't think it could be. I checked the battery two days ago. It must be other problems. 
  #Person1#: Well, I suppose it could be the gas. 
  #Person2#: No, there is plenty of gas. I filled it up yesterday. 
  #Person1#: Perhaps it's the starter then? 
  #Person2#: Yes, that's possible.