I will never understand how it         that you were an hour late on such a short journey.

I will never understand how it         that you were an hour late on such a short journey.

    A．came about       B．came across      C．came out         D．came up with

I will never understand how it         that you were an hour late on such a short journey.

1. A.
   came about
2. B.
   came across
3. C.
   came out
4. D.
   came up with

I will never understand how it __________ that you were an hour late on such a short journey.

A. was happened    B. came about   C. took the place    D. came out