proficient

Good at something; skilled; fluent; practiced, especially in relation to a task or skill.

• He was a proficient writer with an interest in human nature.

An expert.

• The colonel now addressed me, […] adding, "I hope we shall send you to your regiment up the country quite a proficient, and calculated to reflect credit on your instructors in the Zubberdust Bullumteers."
• Why not subpoena as well the clerical proficients?