Study your stems!

Current Stems:

lun- moon (lunar, circumlunar, lunatic)

phon- sound (telephone, cacophony, dictaphone)

mis - hate (misanthropic, misogynist, misery)

spir- breathe (respiratory, perspiration)

ject- throw (eject, reject, project)

Past Stems:

trans- across (transportation, transfer, Transatlantic)

duc/duct- lead (producer, conductor, deductive)

capit- head (decapitation, captain, recapitulate)

greg- group (congregation, gregarious, egregious)

aqua- water (aquatic, aquamarine, aquarium)

astro- star (astrology, astronomical, astronaut)

chron- time (chronological, chronicle, chronic, chronometer)

poly- many (polygon, polytheistic, polygamy)

intra- within (intrastate, intracellular, intervenously)

ic/ical- having the characteristics of (heroic, allergic, frantic, statisical)

proto- first (prototype, protoplasm, protogenitor)

gen- origin (genetics, gene, protogenitor)

intro- into (intruder, introduction, introvert, introspective)

ver-truth (verify, aver, veracious, verdict)

super-over (supercede, superb, superior)

matri-mother (matricide, matron, maternity)

phyt-plant (phytography, phytologist)

cred-believe (credibility, discredit, incredible)

ness-quality (kindness, redness, stillness)

frater-brother (fraternity, fraternize, fraternal)

omni-all (omipotent, omnivore, omniscient)

eco-house (ecosystem, economy, ecology)

zo-animal (zoology, zoo, Mesozoic)

corp-body (corpulent, incorporeal, corporation)

muta-change (immutable, mutant, mutagen)

pater/patri-father (patronize, paternal, patriarch)
mono-one (monologue, monocle, monogamy)
demo-people (democracy, demography, democratic)
ex-out (exit, exclude, extreme)
liber-free (liberty, liberate, liberation)cian-specialist (pediatrician, mathematician, magician)
cide-kill (homicide, suicide, insecticide)
logy-science (psychology, geology, biology)
meter-measure (thermometer, chronometer, barometer, speedometer)
scope-look (microscope, telescope, periscope)

Future Stems: