—Have you been to the Great Wall?
—Perhaps not in my memory.________，it might have been during my early childhood.
| A．If any | B．If so |
| C．If ever | D．If not |
. He misunderstood _____ I said.
| A．that | B．when | C．where | D．what |
. The trouble is _____ we are short of hands.
| A．what | B．that | C．how | D．why |
The guide showed the travelers _____ of the factory.
| A．in | B．out | C．off | D．around |
We should mind our behaviour ______ public.
| A．at | B．in | C．on | D．out |
Excuse me, I have no ______ on me. Can you _____ the note of 100 yuan ?
| A．changes, charges | B．changes, change |
| C．change,change | D．changed, changed |