clamp down on (?.)

• asphyxiate
• beat down
• bottle up
• break
• browbeat
• bulldoze
• bully
• castrate
• censor
• choke off
• coerce
• compel
• cork
• cork up
• cow
• crack down on
• crush
• damp down
• daunt
• despotize
• domineer
• domineer over
• drown
• enslave
• extinguish
• gag
• grind
• grind down
• henpeck
• hold down
• intimidate
• jump on
• keep down
• keep under
• kill
• lord it over
• muzzle
• oppress
• overawe
• overbear
• overmaster
• override
• pour water on
• press heavy on
• put down
• quash
• quell
• quench
• repress
• ride over
• ride roughshod over
• shut down on
• silence
• sit down on
• sit on
• smash
• smother
• squash
• squelch
• stanch
• stifle
• strangle
• stultify
• subdue
• subjugate
• suffocate
• suppress
• terrorize
• throttle
• trample down
• trample upon
• tread down
• tread upon
• tyrannize
• tyrannize over
• unman
• walk all over
• walk over
• weigh heavy on