well-versed (?.)
- abreast of
- adept in
- at home in
- au courant
- briefed
- educated
- enlightened
- expert at
- good at
- handy at
- informed
- instructed
- master of
- posted
- primed
- proficient in
- schooled
- skilled in
- strong in
- taught
- trained
- up on
- up-to-date
- versed
- versed in
- well up on
- well-educated
- well-grounded
- well-informed
- well-posted
- well-read
- widely read