Had they known what was coming next, they _________second thoughts.
| A．may have | B．could have |
| C．must have had | D．might have had |
You will find the game is not so difficult to play ______ you understand its rules.
| A．until | B．since | C．before | D．once |
The building, ______ in the shape of an egg, is now just for tourists.
| A．designing | B．designed | C．to be designed | D．having designed |
Remember to take a breath of ______ fresh air and have some exercise each day. It will make ______ difference.
| A．/；a | B．the；a | C．/；the | D．a；the |
—Would you like to meet John at the airport?
—________. He is the last person I want to see.
| A．Yes, I’d like to | B．I’d like to, but I have no time |
| C．Oh, no, not me | D．With pleasure |
He had planned to make a compromise, but ______ he changed his mind at the last minute.
| A．therefore | B．somehow | C．anyhow | D．otherwise |