Cloning an animal is a complex ________ that can go fatally wrong at any stage.
| A．process | B．regulation | C．step | D．method |
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 |
—What are you busy with?
—The conference _____in our city next week, as you know.
| A．held | B．will be held | C．be holding | D．to be held |
Do you really want to borrow the old room which is empty _____a broken desk and a chair?
| A．except | B．except for | C．except that | D．besides |