The perforator is a three-way connecting piece, two openings of the perforator are upwards parallel, and one opening is downward and is made into an oblique opening.
其特征在于打孔器为三通联接件，其两口平行向上，一口向下并做成斜口；
2
A three-waypiece which causes the main ear piece, the auxiliary ear piece and the chest piece to communicate is connected in the bottom rubber pipe of the stethoscope for teaching.
该示教听诊器在下胶管中都接有一个将主、副耳件及胸件接通的三通接头。
3
Behind you, between briefcases and three-piece suits, an old man with his caged bird makes his way to morning tea.