In order to get the exact result, the scientists made _______.
| A．a lot tries | B．to do experiments | C．trial and error | D．great try |
--___ do you want? --I want a book on history.
| A．Which books | B．What book | C．How many books | D．Whose book |
Shortly after the accident, two ___ police were sent to the spot to keep order.
| A．dozens of | B．dozens | C．dozen | D．dozen of |
Mr. Wang said that he ___ next year.
| A．will go abroad | B．would go abroad | C．will go to abroad | D．would go to abroad |
In the dark street, there wasn’t a single person ___ she could turn for help.
| A．that | B．who | C．from whom | D．to whom |
Jennifer hates to do her homework.In fact, no one ___it.
| A．ever really enjoys doing | B．really is ever enjoying to do | C．enjoy to really ever do | D．really ever enjoys to do |