最早用白虎加人参汤、肾气丸治疗消渴的医家是（）
A．张景岳
B．张仲景
C．张子和
D．严用和
E．叶天士
参考答案：B
无粘结预应力混凝土是一项先张法新工艺。( )
— You seem familiar with Mr. John?
—Of course, we _________ together for three years in the 1990s.
A．have worked
B．were working
C．are working
D．worked
