Check words you know to measure your vocabulary size (number of word families).
worth
chicken
hard
neighbour
rely
plane
complain
gentleman
allocate
reproduce
potential
stake
armour
veterinarian
basement
hollow
junk
buckle
thereafter
asylum
freelance
cavalry
plume
whine
taut
proficient
motel
orchid
pervade
macroeconomic
clandestine
blurt
moderated
crucify
seconded
provenance
loony
renege
philanthropy
spleen
autonomic
pliers
sputter
transgenic
turpentine
enfold
canton
pharisee
tiara
prevaricate
jilt
castor
phosphor
spats
afire
potpourri
aspersion
shew
vouchsafe
valerian
schizoid
concordat
lepton
rubella
scape
gherkin
minim
baulk
curiae
ultrastructural
calabash
kinesiology
kwanza
standpipe
filaria
terrazzo
clangour
empiric
muntjac
autogyro
bacteremia
disa
nunciature
limnology
disunion
loganberry
whippoorwill
klatch
awhirl
kultur
perse
trematode
banca
microbot
corrody
erbium
mephitis
bobolink
carpi
guck