Hisbackacheisonly_________fornotwateringtheflowers.

许多国家在国际收支出现逆差时，利用汇率变动对进出口贸易的作用机制，通过本国货币贬值来()

Thedoctorletthepatients______thesoftmusic,becauseithelpedmakethem_____.

--It’ssaidthatallthehotelsarefilledwithtourists.

--Don’tworry!I_________aroominMianzhouHotel.

实对称矩阵所，如下图，对应的二次型f(x1,x2,x3)=______