I will buy this type of car _____ the price is brought down to under 10,000 dollars.
A. even if B. provided that 
unless D. whether
he thought he was helping us with the work, he was actually in the way.
| A．Although | B．Unless | C．Because | D．When |
Hearing his words ,I couldn’t decide or remain .
| A．whether to go abroad | B．if I go abroad |
| C．if to go abroad | D．to go abroad |
Questions and exercises are given by the computer, which decides ______ to move the students ahead, review an easier level, ____ give more work on the same level.
| A．either, or | B．both, and . | C．whether, or | D．not only, but also |
—Will you go to Mary’s birthday party?
—No, ____ invited, I can’t go to it. I’ll be too busy then.
| A．if | B．unless | C．even though | D．when |
The librarian promised to get the book for me ____she could remember who last borrowed it.
| A．in case | B．if only | C．even if | D．ever since |