It is written clearly in the requirements that all passengers check onto board thirty minutes before the plane takes off.
| A．may | B．can | C．will | D．shall |
Every possible means_____ been tried，and we find only______ this means can we do it well．
| A．have，in | B．have，by |
| C．has，in | D．has，by |
Because of too many differences between the two sides, a lot of questions are still left ________.
A in the airB on the airC by the airD through the air
______ it is to learn English on the internet!
| A．What a fun | B．What fun | C．How a fun | D．How fun |
Would you____holding this box for me while I open the door?
| A．care | B．like | C．mind | D．matter. |
Most of us know we should cut down fat, but knowing such things isn’t much help when it____shopping and eating.
A refers to B. speaks of C. focuses on D. comes to