1. split into two opposite groups.   ruminate   perturb   validate   polarize   Hint Half-n-half Clue   2. hinder or prevent.   solder   simulate   inhibit   ossify   Half-n-half Clue   3. make valid or confirm.   vaporize   truncate   incorporate   validate   Half-n-half Clue   4. make pulp by chewing.   imply   interpolate   masticate   wane   Half-n-half Clue   5. pierce or make hole(s) in.   wax   infer   pulverize   perforate   Half-n-half Clue   6. cut the tip off.   probe   manipulate   simulate   truncate   Half-n-half Clue   7. interject or insert between.   interpolate   impinge   manipulate   probe   Half-n-half Clue