Not until he met with the difficulty _______ the importance of group work.
| A．he realized | B．did he realize | C．realized he | D．he didn’t realize |
．—you got to know where I was yesterday?
—Through a student.
| A．Where was it that | B．When was it that |
| C．How was it that | D．Was it how that |
Scotland liesthe north of England, it isof Britain.
| A．to; part | B．on; the part | C．in; part | D．to; the part |
When lastvaluable, those books enjoyed great success.
| A．finding | B．found | C．being found | D．to be found |
He knows little of mathematics, of chemistry.
| A．and still less | B．as well as | C．and still more | D．no less than |
Discovering consists of seeing what everybody has seen andwhat nobody has thought.
| A．think | B．thinking | C．thought | D．to think |