为什么要挡渣出钢？

北京市某天上午的温度是-5℃，中午又上升了8℃，下午由于冷空气南下，到夜间又下降了9℃，则这天夜间的温度是______℃．

----Have you ever seen Peter recently ?

---Yes . He _____ me to ask you how you _____ along with your new job these days .

A．has asked ; have been getting

B．asked ; were getting

C．often asks ; are getting

D．asked ; are getting

从性别角度而言，惯习和风俗通过一系列的理念和形式，把性别文化固定下来，规范人们的性别行为。

小额支付系统（）业务，轧差净额清算资金。

光衰耗器是一种用来（）的无源器件。