When ________how a statue from distant Greece，in China，researchers explained that it was no doubta result of Alexander the Great’s influence．
| A．they were asked；should appear； |
| B．being asked；can have appeared； |
| C．asked；must have appeared； |
| D．asked；could have appeared； |
Shall Mary come to the concert with us？
－Notshe has finished her paper．
| A．since | B．once | C．when | D．unless |
Water, _______enough, can change into vapour quickly.
| A．when heated | B．heating | C．though to be heated | D．when is heated |
The man stopped from time to time_______whether he was being followed.
| A．as if found | B．as to find | C．as if to find | D．when found |
Doctors have said that as many as 50% of patients don’t take medicine_______.
| A．like directed | B．to be directed | C．as directed | D．so that directed |
You may take them all home_______.
| A．if possible | B．if can | C．unless so | D．even if you can |