You can’t imagine the difficulty he _____ onto the cliff and saving the boy in trouble.
| A．had to climb | B．had climbed | C．had climbing | D．had on climbing |
Nowadays people sometimes separate their waste to make it easier for it ______. .
| A．reusing | B．reused | C．reuses | D．to be reused |
She is very dear to us. We have been prepared to doit takes to save her life.
| A． | whichever | B． | however | C． | whatever | D． | whoever |
Would you please keep silent? The weather report andI want to listen.
| A． | is broadcast | B． | is being broadcast |
| C． | has been broadcast | D． | had been broadcast |
The collapse of the World Trade Centre has put US economy in a difficult___________.
| A．occasion | B．case | C．situation | D．background |
More and more people choose to shop in a supermarket as it offers a great _______of goods.
| A．variety | B．mixture | C．extension | D．combination |