A new technique ____ out, the yields increased by 20% .
| A．having working | B．having been working |
| C．has worked | D．had been worked |
“Are you satisfied with his answer?”“Not at all. It couldn’t have been ____.”
| A．better | B．worse |
| C．more | D．less |
Tom’s mother always told him not to smoke again, but _____ didn’t help.
| A．he | B．it |
| C．which | D．as |
In my apartment there are two rooms, _____ is used as a living room.
| A．larger one | B．the larger of which |
| C．the largest one | D．the largest of which |
There was nothing special about this film — it was only ______.
| A．particular | B．average |
| C．interesting | D．strange |
I don’t like it at all. It can’t be _____.
| A．better | B．worse |
| C．best | D．worst |