_____will you stay in America? About two weeks.
A.How many B. How often C. How long
I never doubt ______ the science museums are worth_______.
| A．whether，visiting | B．that, to visit |
| C．whether , a visit | D．that ,a visit |
-----Jenny, you should prepare as much as you can______ the coming guitar competition successfully!
-----Sure, I will try my best, Mr. Brown!
| A．to fail | B．to cover |
| C．cover | D．fail |
-----Wow, Anna, you look so great in your new coat!
-----Thanks. I ______ it when it was on sale.
| A．bought | B．have bought |
| C．buy | D．had bought |
You had better say “Thank you” when you __________ with the medal.
| A．present | B．presented |
| C．are presented | D．were presented |
-----Jack, could you help me _______ more information about the bad effects of the hazy weather on the Internet?
-----With pleasure
| A．put up | B．make up |
| C．take up | D．look up |