1. cred, credit = to believe
Words
incredulous - not believing, skeptical
credulity - gullibility
credence – belief
creed – belief
credulous - gullible

2. curr, curs = to run Words excursion - journey cursory - brief
precursor – forerunner
current – existing (running) now, flow of water
incur – to experience or acquire (usually unpleasant, such as to incur expenses)

3. dem = people Words democracy – rule of the people
demagogue – false leader of the people
epidemic – widespread (among the people)

4. derm = skin Words epidermis - skin pachyderm – thick-skinned quadruped
dermatology – study of skin and its disorders
hypodermic – involving area beneath the skin

5. dic, dict = to say Words abdicate - renounce
diction – speech, word choice
verdict – statement of jury
edict – a decree
benediction - blessing, good wishes (“good say”)

6. doc, doct = to teach Words docile - obedient; easily taught
document – something that provides evidence
doctor – a learned person (a teacher)
doctrine – rule or principle

7. duc, duct = to lead
Words
induct – to install one into office (to lead into)
deduct – to subtract (to lead away)
seduce – lead aside
duct – a channel or tube through which something can flow or be carried

8. ego = I Words egotist – selfish person
egocentric – revolving around one’s self
egomaniac – obsession with one’s self (dangerously so)

9. err = to wander Words error - mistake
erratic - changing directions, wandering, not predictable
errant – wandering from an intended course, unacceptable behavior

10. eu = good, well Words eulogy – spoken or written tribute
euphoric – extremely happy or excited
euphemism – a less offensive term
euphonic - a pleasant sound