____ his telephone number, she had some difficulty getting in touch with Bill.
| A．Not knowing | B．Knowing not |
| C．Not having known | D．Having not known |
On the table she found a piece of paper _________some puzzling secret codes.
| A．which was written | B．that was written |
| C．on which were written | D．on that were written |
The number 9.11 is a special number, ____, I think, that will be remembered by the Americans forever.
| A．what | B．it | C．which | D．one |
We are going to discuss the way of reading works ____ it is used for real life purposes, and this should give you a better understanding of it.
| A．that | B．which | C．where | D．when |
— I can’t find Mr Brown. Where did you meet him this morning?
—It was in the hotel _______ he stayed.
| A．that | B．which | C．where | D．when |
He was honest and told us ______ he knew.
| A．that that | B．what what |
| C．all all | D．which which |