______ as an Olympic event, a sport must be played in at least 75 countries in at least 4 continents.
| A．To accept | B．Having accepted |
| C．To be accepted | D．Accepting |
Our teacher said to us that the earth _________ around the sun.
| A．travelled | B．travels | C．is traveling | D．was traveling |
While _________, people sometimes can’t help buying something they don’t really need.
| A．shopped | B．being shopped | C．to shop | D．shopping |
Alexander tried to get his work ______ in the medical field.
| A．to recognize | B．recognizing | C．recognized | D．recognize |
You __________ buy a gift, but you can if you want to.
| A．must | B．mustn’t | C．have to | D．don’t have to |
John thinks it won’t be long ________ he is ready for his new job.
| A．when | B．after | C．before | D．since |