GEN – birth, class, kin

generation

congenital

homogeneous

heterogeneous

ingenious

engender

progenitor

progeny

GRAD, GRESS – step

graduate

gradual

retrograde

centigrade

degrade

gradation

gradient

progress

congress

digress

transgress

ingress

egress

GRAPH, GRAM – writing

biography

bibliography

epigraph

grammar

epigram

GRAT – pleasing

grateful

gratitude

gratis

ingrate

congratulate

gratuitous

gratuity

GRAV, GRIEV – heavy

grave

gravity

aggravate

grieve

aggrieve

grievous

GREG – crowd, flock

segregate

gregarious

egregious

congregate

aggregate