19世纪中后期在中国出现的交通工具有
①火车②飞机③汽车④轮船[ ]
A．①②③
B．①②④
C．③④
D．①④
答案：D
牙周脓肿的特点是
A．脓肿弥散B．牙髓无活力C．牙齿不敢咬合D．X线片上根尖区有阴影E．脓肿局限于牙周袋壁区
In relation to the Vietnamese legal system:
(b) Describe how draft bills and resolutions become law. (4 marks)
