He tried his best to solve the problem, ________ difficult it was.
| A．however | B．no matter | C．whatever | D．although |
If the way _____ you think of is not good enough, you can learn the way ______the top students deal with their study.
| A．in which; / | B．which; which |
| C．that; which | D．/; / |
By the time I got to the office, the meeting ______.
| A．had begun | B．began |
| C．was beginning | D．would begin |
_______ David says sounds right to Helen. That’s why she has made up her mind to live with him____ happens.
| A．Whatever; whatever |
| B．No matter what; whatever |
| C．No matter what; No matter what |
| D．Whatever; however |
_________ we have realized the danger of over-consumption, some measures should be adopted as soon as possible.
| A．Now that | B．As long as |
| C．In order that | D．Even if |
Since then the number of people taking driving lessons______20%.
| A．has increased to | B．increases by |
| C．has increased by | D．have increased |