We have various summer camps for your holidays, You can choose ____ based on your own interests.
| A．either | B．each | C．one | D．it |
With more forests being destroyed, huge quantities of good earth _____each year.
| A．is washing away | B．are being washed away |
| C．are washing away | D．is being washed away |
It is reported that the United States uses _____ energy as the whole Europe.
| A．as twice more | B．twice more as | C．twice much as | D．twice as much |
In peace, too，the Red Cross is expected to send help _____ there is human suffering.
| A．whoever | B．wherever | C．whatever | D．however |
Mr. Smith has bought a new house in the country, around _____ some green trees.
| A．which is | B．it is | C．which are | D．them are |
I'd like to have visited the Palace Museum last week, but something unexpected _____to my father.
| A．had happened | B．happened | C．has happened | D．happens |