Nobody is allowed to go through the between China and Russia without a passport.
| A．booth | B．bush |
| C．border | D．buffet |
It is uncertain ______ the experiment is worth doing .
| A．where | B．that | C．whether | D．how |
I’d like to work with ____ is honest and easy to get on with.
| A．who | B．whoever | C．whomever | D．no matter who |
Mary wrote an article on __the team had failed to win the game.
| A．why | B．where | C．what | D．which |
Do you have any idea ___ is actually going on in the classroom?
| A．that | B．what | C．as | D．which |
If one of the computers _______, the whole networks would be unable to work.
| A．broken down | B．broke up | C．broke out | D．broke in |