Mark needs to learn Chinese _______ his company is opening a branch in Beijing.
| A．unless | B．until | C．although | D．since |
Don’t be afraid of asking for help ______it is needed.
| A．unless | B．since | C．although | D．when |
He made a mistake, but then he corrected the situation ______it got worse.
| A．until | B．when | C．before | D．as |
The thought ______he might be a scientist some day encouraged him to study hard.
| A．whether | B．that | C．how | D．why |
There is a new problem involved in the popularity of private cars ______road conditions need______.
| A．that; to be improved | B．which; to be improved |
| C．where; improving | D．when; improving |
—I promise that she ______ get a nice present on her birthday.
—It will be a big surprise to her.
| A．should | B．must | C．would | D．shall |