涎腺的腺泡分________、________以及_______三种。
参考答案：浆液性腺泡；黏液性腺泡；浆液一黏液混和性腺泡
Your cousin is said ____ a new computer programme recently, but do you know when he will finish it?
A．to design
B．to be designing
C．to have been designing
D．to have designed
纯净的赤铁矿全铁品位是（）。
