The country has already sent up three unmanned spacecraft, the most recent__at the end of last March.
| A．has been launched | B．having been launched |
| C．being launched | D．to be launched |
The old town has narrow streets and small houses _______ are built close to each other .
| A．in which | B．where | C．what | D．that |
We have made _______great progress in the medical field, but ______ progress we have made is not enough.
| A．a; a | B．a; the | C．/; the | D．/; / |
I have many foreign friends, some are businessmen.
| A．of them | B．from which | C．who of | D．of whom |
He used to ______ cards, but now he is used to _______ a walk after supper.
| A．play; taking | B．playing; take | C．play; take | D．playing; taking |
She is considered ___________ the work ahead of time.
| A．finishing | B．to finish | C．having finished | D．to have finished |