实验室里有一瓶标签残缺的盐酸.为能立即确定它是否为浓盐酸,你认为下列做法合理的是( )
A:猜想假设
B:查阅资料
C:进行试验
D:交流讨论
____ ____going to buy the coat.
The teacher walked into the classroom a smile on his face.