She let the children ______ to play instead of staying at home all the time.
| A．going out | B．went out | C．to go out | D．go out |
Only by practicing every day ___________ English well.
| A．can we learn | B．we can learn | C．did we learn | D．learn we |
Only when 1 was fourteen__________the importance of study．
| A．I realized | B．did I realize | C．had I realized | D．I had realized |
Only after the plane had taken off _________ that he missed his parents so much.
| A．he found | B．he had found | C．did he find | D．was he found |
Only when I left my parents for Italy __ how much I loved them.
| A．I realized | B．I had realized |
| C．had I realized | D．did I realize |
So much of interest ___ that most visitors simply run out of time before seeing it all.
| A．offers Beijing | B．Beijing offers |
| C．does Beijing offer | D．Beijing does offer |