高中英语,完成句子HealwayssuggeststhatIshouldputthebooks__________(belong)他总是建议我要HealwayssuggeststhatIshouldputthebooks__________(belong)他总是建议我要把书放回原处.答案是wheretheybelong为什

　　高中英语,完成句子HealwayssuggeststhatIshouldputthebooks__________(belong)他总是建议我要

　　HealwayssuggeststhatIshouldputthebooks__________(belong)

　　他总是建议我要把书放回原处.

　　答案是wheretheybelong

　　为什么不是wheretheybelongto请详解