It is obvious to the students ______ they should get well prepared for their future.
| A．as |
| B．which |
| C．whether |
| D．that |
I wish to thank Professor Smith, without _______help I would never have got this far.
| A．who | B．whose | C．whom | D．which |
The problem, according to the experts, is _______ we should do with the salty land.
| A．that | B．how | C．which | D．what |
He has always insisted on _______ Mr. Berg instead of Justin.
| A．been called | B．called | C．calling | D．being called |
When Peter speaks in public, he always has difficulty ______ the right things to say.
| A．thinking of | B．to think of | C．thought of | D．think of |
As Jack left his membership card at home, he was forbidden ______into the sports club.
| A．going | B．to go | C．go | D．gone |