Unit 1 abnormal--apt
Unit 2 arc--blunder
Unit 3 blunt--chaos
Unit 4 characterize/-ise--concession
Unit 5 concise--cynical
Unit 6 damn--displace
Unit 7 disposition--engagement
Unit 8 enhance--flee
Unit 9 fling--grim
Unit 10 grin--incidence
Unit 11 incidentally--judicial
Unit 12 junction--mechanism
Unit 13 medal--obligation
Unit 14 obscene--perplex
Unit 15 persistent--proposition
Unit 16 prose--refreshment
Unit 17 refuge--sculpture
Unit 18 seam--spectrum
Unit 19 speculate--swap
Unit 20 symmetry--tuck
Unit 21 tug--ward off