The reason why he adapted to the new situations quickly is that he has a _____ attitude.
| A．changeable | B．alternate | C．movable | D．flexible |
certain that his invention will lead to the development of production.
| A．That's | B．This is | C．It's | D．What's |
that she has gone to the United States?
| A．Was it true | B．Is it true | C．It is true | D．It was true |
you met the Englishman?
| A．Where it was that | B．Who it was that | C．Where was it that | D．Where was that |
It was not until 1936 basketball became a regular part of the Olympic Games.
| A．that | B．when | C．which | D．then |
“It” is often used to a baby.
| A．mean to | B．stick to | C．point to | D．refer to |