________ the roof leaks, you have a serious problem.
A: As a result of
B: Therefore
C: Whenever
D: Unless
A: As a result of
B: Therefore
C: Whenever
D: Unless
举一反三
- ________ the roof leaks, you have a serious problem.
- 如果你当时意识到问题的严重性，并采取措施，结果就完全两样了。 A: Have you realized how serious the problem was then and taken some measures, the result is completely different. B: Have you realized how serious the problem was then and taken some measure, the result will have been completely different. C: Had you realized how serious the problem was then and taken some measures, the result would have been completely different.
- _____you may have, you should gather your courage to face the challenge. A. However a serious problem B. What a serious problem C. However serious a problem D. What serious a problem
- _____ you return those books to the library immediately, you will have to pay a fine. A: If B: Unless C: As long as D: Whenever
- Incorrect assembly of the seal will result in leaks the valve. A: If you install the<br/>seal incorrectly, leaks can occur around the valve. B: Incorrect assembly of the seal will result in leaks past the valve. C: If you install the<br/>seal incorrectly, leaks can occur surrounding the valve.