—It’s reported that the new underground line has been completed．
—Yes but it hasn’t been made clear________ it’s to be opened to traffic．
| A．that | B．who | C．what | D．when |
Elephants have their own way to tell the shape of an object and _______ it is rough or smooth.
| A．/ | B．whether | C．how | D．what |
—Why does she always ask you for help?
—There is no one else _______, is there?
| A．who to turn to | B．she can turn to |
| C．for whom to turn | D．for her to turn |
Do you have any idea _______ is actually going on in the classroom?
| A．that | B．what | C．as | D．which |
Mary wrote an article on _______ the team had failed to win the game.
| A．why | B．what | C．who | D．that |
Doris' success lies in the fact _______ she is co-operative and eager to learn from others.
| A．which | B．that | C．when | D．why |