club (verb) combine, pool
cite(v) mention, quote
challenge(v) confront, dispute, question
challenge(n) trial, problem, test
coast(n) seaside, waterfront
coast(v) drift, taxi, glide, skate, float, cruise
combine(v) pool, club, mix, mingle, join, blend, fuse, incorporate,
consolidate, integrate, unify, compound, merge, unite
comfort(n) repose, content, solace, consolation, relaxation, ease
comfort(v) console
command(n) knowledge, understanding, grasp, grip
Ex: He had a good command of English
command(n) order, directive, instruction, direction
command(v) control, order, tell, charge, direct, instruct
commute(v) shuttle
reduce, lessen, shorten, limit, curtail
common(adj) usual, regular, ordinary, familiar, habitual, frequent
common(adj) public, communal
complete(adj) whole, total, entire, full
absolute, utter
complete(v) finish, accomplish