In the film clip, we can see a train is carrying some women toconcentration camp. The white-and-black color, plus the flashing and changing of shadow and light can create an atmosphere of all except _________.
【简答题】阅读短文,从A-F中选出正确答案。 A. Causes of dental fluorosis B. Negative effects of fluoride C. Safe use of fluoride D. The expert's background information E. No need to worry about fluoride poisoning F. Solutions...