防洪运用标准

一种商品打七折销售．“七折”表示______是______的70%．

在同一平面内，相交的两条直线不一定互相垂直______．

After the flood, the villagers began to ______ and tried their best to rebuild their homeland.

A．look up

B．look back

C．look around

D．look ahead

—             do you have an English party?

—Once a month.[ ]

A. How

B. How often

C. How long

D. How old

预留印鉴卡片由专人保管，坚持（）。

A.谁保管谁核对

B.谁使用谁核对

C.谁核对谁签章