There are some health problems that，when ________ in time，can become bigger ones later on. (2013·浙江，19)
| A．not treated | B．not being treated |
| C．not to be treated | D．not having been treated |
Sorry, we are late,--our plane was _____ because of the heavy rain.
| A．held out | B．held on | C．held up | D．held back |
I’d like to have visited the Palace Museum, but something unexpected _______ to my father.
| A．had happened | B．happened | C．has happened | D．happens |
－What are you busy with ?
－The conference _______ in our city next week.
| A．held | B．will be held | C．be holding | D．to be held |
Attention, coffee lovers! We have for you, the best coffee machine _____ invented.
| A．ever | B．already | C．even | D．nowadays |
Can you imagine what difficulty people had this year_______________against thesevere naturaldisasters?
| A．fighting | B．to fight | C．fought | D．fight |