观察是研究物质性质的一种基本方法．一同学将一小块金属钠露置于空气中，观察到下列现

I remember seeing this kind of _______ product in _______ city of Shanghai, which is known as _______ Paris of the East.

A．the; the; the

B．/; the; the

C．the; /; the

D．the; a; /

— Do you like the new jacket? 

— Yes, I _____. [ ]

A. am

B. do

C. does

D. like

通常前牙金属烤瓷冠唇面龈边缘的最佳选择是

A．龈上凹形边缘
B．龈下肩台边缘
C．龈上肩台边缘
D．龈下凹形边缘
E．平龈边缘

体育锻炼对呼吸系统的作用？

合成废锅电导高，可加入联胺进行调节。