What's the base word in "mistake"
take
What's the base word in "redo"
do
What's the base word in "preview"
view
What's the base word in "bicycle"
cycle
What's the base word in "misuse"
use
What's the base word in "reread"
read
What's the base word in "rebuild"
build
What's the base word in "tricycle"
cycle
What's the base word in "rewrite"
write
What's the base word in "refill"
fill
What's the base word in "misspeak"
speak
What's the base word in "unicycle"
cycle
What's the base word in "misunderstand"
understand