治疗温热病邪在气分，壮热、烦渴、汗出、脉洪大等证时，常相须为用的药物是（）
A.石膏
B.栀子
C.知母
D.丹皮
E.黄柏
参考答案：A, C
已知P是矩形ABCD所在平面外一点，∠PAB=∠PAD=90°，PA=12，AB=3，AD=4．
（1）求证：PA⊥BD．
（2）求线段PC的长．
---Why did Suzy look so stressed when we saw her?
---Because she wondered________.
A．what her sister has done during the trip
B．when would her father come back
C．if she had passed the driving test
D．where did the other friends do
