下列糖皮质激素类药物中抗炎作用最强的是
A．泼尼松
B．泼尼松龙
C．地塞米松
D．可的松
E．氢化可的松
参考答案：C
As we all know, the next summer Olympic Games _____ in London in 2012. [ ]
A. will hold
B. will be held
C. is to hold
D. are held
伸缩式液压缸有什么特征？
