Prefix -in
Prefix -non
Prefix mis-
Prefix sub-
Double the Points
(Extra Difficult)
100

not done

incomplete

100

doesn't make sense

nonsense

100

to act bad

misbehave

100

underground train

subway

100

lack of action or activity

inaction

200

having grown within.

ingrown

200

a business that doesn't earn money

nonprofit

200

to not get or comprehend

misunderstand

200
underwater vehicle

submarine

200

not able to be replaced

irreplaceable

300

not formal

informal

300

ongoing, continuing

nonstop

300

to label wrong

mislabel

300

captions at the bottom of a move or television screen

subtitle

300

active against bacteria

antibacteria

400

a plane in the the sky

inflight

400

having not items made from milk

nondairy

400

past tense of mistake

mistook

400

the foundation for a floor in a building

subfloor

400

Existing outside or beyond the earth.

extraterrestrial

500

not safe

insecure

500

not sticking 

nonstick

500

to take a wrong turn or path, to make a mistake

misstep

500

a part of a larger group of related things

subset

500

not able to understand or comprehend

incomprehensible

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