New technologies have made __________ possible to turn out new products faster and at a lower cost.
| A．that | B．this |
| C．one | D．it |
Not once________to Michael that he could one day become a top student in his class.
| A．occurred it | B．it did occur |
| C．it occurred | D．did it occur |
“Never for a second，”the boy says，“________ that my father would come to my rescue.”
| A．I doubted | B．do I doubt |
| C．I have doubted | D．did I doubt |
At no time ________the rules of the game.It was unfair to punish them.
| A．they actually broke |
| B．do they actually break |
| C．did they actually break |
| D．they had actually broken |
Not until he went through real hardship ________the love we have for our families is important.
| A．had he realized | B．did he realize |
| C．he realized | D．he had realized |
Only by increasing the number of doctors by 50 percent ________ properly in this hospital.
| A．can be the patients treated |
| B．can the patients be treated |
| C．the patients can be treated |
| D．treated can be the patients |