C1 adverbs

Abrupt

sudden and unexpected

Adept

very skilled or good at something

Ambiguous

unclear; can have more than one meaning

Apparent

obvious; easy to notice

Arbitrary

based on personal choice, not reason

Authentic

real or genuine

Cohesive

well-connected; forming a unified whole

Comprehensive

complete; covering everything important

Conspicuous

very noticeable

Contemporary

modern; from the present time

Contrary

opposite

Conventional

traditional; usual

Crucial

extremely important

Cumulative

increasing over time

Detrimental

harmful or damaging

Discreet

careful and private

Diverse

varied; different

Dubious

doubtful; suspicious

Elaborate

detailed and complex

Eminent

famous and respected

Equitable

fair and equal

Erratic

unpredictable

Explicit

clear and direct

Feasible

possible or realistic

Hostile

unfriendly or aggressive

Hypothetical

based on theory, not facts

Imminent

about to happen soon

Implicit

suggested but not said directly

Inadequate

not enough

Incessant

nonstop; continuous

Independent

not controlled by others

Indignant

angry because something is unfair

Innovative

new and creative

Integral

essential and necessary

Intricate

complex; detailed

Lucrative

profitable

Marginal

small or unimportant

Notorious

famous for something bad

Objective

based on facts

Pivotal

extremely important

Plausible

believable

Predominant

most common or powerful

Prosperous

successful and wealthy

Rational

logical

Resilient

able to recover quickly

Sophisticated

advanced or elegant

Subtle

not obvious

Substantial

large or important

Tangible

real; can be measured

Vulnerable

easily harmed