不能安全使用一个检验周期的气瓶和阀门应予报废
正确
暂无解析
设函数f(x)=1-x^2在区间(,)
________tothepapersisrestrictedtoDefenseDepartmentpersonnelonly.
Thosewho’dliketovisittheexhibition________(sign)yournameshere.
Heaskedmewhethermybrother________(fly)toBeijing.
Thisdiploma(毕业文凭)________thatyouhavecompletedhighschool.
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