Sentence:  “My Continental prominence is <WSD>improving</WSD>,” I commented dryly. ¶ Von Lindowe cut at a furze bush with his silver-mounted rattan. ¶ “Quite so,” he said as dryly, his hand at his mustache. “I may say if your intentions were known your life would not be worth a curse.” 
Meaning of the word marked with <WSD> tags:  To become better.