While cleaning the snow on the road, _________.
| A．a wallet was found on the ground. | B．a wallet appeared on the ground. |
| C．I found a wallet lying on the ground. | D．I found a wallet laid on the ground. |
It is the protection for the trees _______ really matters, rather than how many trees are planted.
| A．what | B．that |
| C．不填 | D．which |
It is _______ he often fails in exams ______ makes his parents worried about him.
| A．what； that | B．that； what |
| C．that； that | D．/ ； that |
—Who are making so much noise in the garden？
—_______ the children.
| A．It is | B．They are |
| C．That is | D．There are |
It was lack of money, not of effort, _____ defeated their plan.
| A．which | B．as |
| C．that | D．what |
It’s more than half a century _____ my grandfather joined the Party and became a servant to the people.
| A．when | B．that |
| C．since | D．while |