How did it ________ that the ancient building was burnt down in an hour?

1. A.
   happen
2. B.
   occur
3. C.
   take place
4. D.
   come about

         —How did it _____ that you made such a silly mistake?

—I myself haven’t figured it out yet.

A. bring about   B. come about  C. come across D. come on

How did it _____ that the two men arrived to address the same meeting at the same time.

　　A. fall out  B. take place C. get around  D. come through

－How did it        that the secretary knew where we were?

－Maybe he had been following us.

A．come about        B．come across       C．come off          D．come round

–How did it ____that you missed the bus ?

- I’m sorry I got up late.