Othersarguethatsincetheearthhasenduredalongstringoficeagesinthelasttwomilliontothreemillionyears,anywarmingis________tobetemporary.
A、seemedHumanbehaviorismostlyaproductoflearning________thebehaviorofanimalsdependsmainlyoninstinct.
Attendanceatfootballmatcheshave_____sincethecomingoftelevision.
It'smore________tobuyaseasonticketifyoutraveleveryday.
Othersarguethatsincetheearthhasenduredalongstringoficeagesinthelasttwomilliontothreemillionyears,anywarmingis________tobetemporary.
Becareful,_______you'llfalldown.
