——This wall of air is an effective answer to the problem and it ____ work.
——But it is a question to put such a wall of air around the statue.
| A．may | B．must | C．should | D．could |
Not having found __________，he had to go home with empty hands．
| A．something | B．everything | C．anything | D．nothing |
(2014届陕西省西工大附中高三第五次适应性训练英语试卷）
It was hard for him to learn English in a family, in which_____ of the parents spoke the language.
| A．none | B．neither | C．both | D．either |
（2011北京卷,34﹚The employment rate has continued to rise in big cities thanks to the efforts of the local governments to increase .
| A．them | B．those | C．it | D．that |
The two girls are so alike that strangers find_____ difficult to tell one from the other.
| A．it | B．them | C．her | D．that |
（2011重庆卷,27﹚——Silly me! I forget what my luggage looks like.
——What do you think of over there?
| A．the one | B．this | C．it | D．that |