–What should parents do when their children have some problems?
--I think it’s ____ for them to be there with their children.
| A．impossible | B．important | C．impolite | D．difficult |
Children wake up very early ____ the morning of Christmas Day.
| A．in | B．on | C．for | D．at |
____ a cold winter morning, I met her in the street.
| A．In | B．On | C．At | D．For |
Why did you get up so early ___ this morning.
| A．on | B．/ | C．at | D．in |
The Eiffel Tower __________ for the 1889 Paris Expo. It is a symbol of the city now.
| A．built | B．was built | C．has built | D．was building |
Could you please tell me ___________?
| A．whose book is this | B．whose book was this |
| C．whose book this is | D．whose book this was |