Theoppositionleaders________thegovernmentfornottakingactionsooner.
Humanbehaviorismostlyaproductoflearning________thebehaviorofanimalsdependsmainlyoninstinct.
GeneralMotors,oneoftheworld'slargestautomanufacturers,isexpandingits________inthiscountry.
TheTVstation,in________tomassivepopulardemand,decidedtocontinuethesoapopera(肥皂剧).