1. diplomatic   SAVORY   TACTFUL   SUSCEPTIBLE   TENACIOUS   Hint Half-n-half Clue   2. slow-moving   UNOBTRUSIVE   UNKEMPT   SERVILE   SLUGGISH   Half-n-half Clue   3. trivial   SUPERFICIAL   TRIFLING   SEDENTARY   SUSCEPTIBLE   Half-n-half Clue   4. not done before   TANTAMOUNT   UNPRECEDENTED   SOMBER   SUSCEPTIBLE   Half-n-half Clue   5. gloomy   STAGNANT   WARY   SOMBER   SCRUPULOUS   Half-n-half Clue   6. stealthy   VOLUBLE   TENTATIVE   SURREPTITIOUS   SCRUPULOUS   Half-n-half Clue   7. occurring irregularly   VENERABLE   SPORADIC   TACITURN   SLUGGISH   Half-n-half Clue