6. Years ago this politician did a clever， but ﹙immoral ﹚thing， which laid the foundation of his fortune.

　　A. unethical

　　B. unexpurgated

　　C.unimpeachable

　　D.improper

　　7. It is always praiseworthy to admit ones errors and﹙ rectify ﹚them without delay.

　　A. straighten

　　B. correct

　　C.justify

　　D.identify

　　8. This special task calls for common sense， imagination， intelligence and﹙ tact.﹚

　　A. prudence

　　B. bravery

　　C.diplomacy

　　D.coolness

　　9. "Do I understand that it is not ﹙compulsory ﹚for us to attend?" Mr. Johnson asked.

　　A. advisable

　　B. obligatory

　　C.indiscreet

　　D.necessary

　　10. Hundreds of years ago cloves were used to ﹙remedy﹚ headaches.

　　A. disrupt

　　B. diagnose

　　C.evaporate

　　D.cure