1) Yes, I sometimes have bad dreams.

2) I always dream during sleep.

3) I occasionally have "weird car dreams," in which I somehow am driving my car while sitting in the back seat--either the car has gotten small or my arms have gotten large--and perhaps I am driving backwards down the highway at 100 kph.

Actually, the strangest thing about dreams is that they really can't be described. In the process of trying to describe them, I distort and change them.

4) The closest thing to repeated dreams are anxiety dreams about being unprepared for classes. One of them is the classic "examination dream," in which it is the end of a semester and I suddenly realize that I registered for a course, forget that I registered, and have attended no classes at all. I need to get to the exam. I am in a huge building that is made up of pieces and rooms and corridors and stairs from every school I have ever been in. I can't find the room number. And although I can't see it, it is hard to walk quickly because the floor is covered a meter deep with invisible syrup.