Don’t answer me with a simple “yes” or “no”. Explain ______possible.
| A．whatever | B．whenever | C．whoever | D．however |
More and more people have come to realize that if we had taken effective measures much earlier, the air quality ______ so seriously now.
| A．is not polluted | B．would not be polluted |
| C．had not been polluted | D．would not have been polluted |
As for friendship, remember that no time is ever wasted _______ makes two people better friends.
| A．what | B．that | C．when | D．as |
The golden rule is not to waste time waiting for opportunity. Begin, ______ opportunity will find you.
| A．and | B．when | C．so | D．because |
---Mom, where is my lunch pack?
---Just where it _______.
| A．has been | B．had been | C．was | D．be |
Some experts argue that the reason why the price of houses can’t drop is that the supply is not ______ to the demand.
| A．adequate | B．sensitive | C．entire | D．accessible |