art.一(个),每一(个),任一(个)
I was assigned to Troop A of the 10th Cavalry.
我被派往第10骑兵队的A连。
Details are available from the Hon. Sec. A.R. Bushby.
详情可咨询名誉秘书A.R.布什比。
Liver and kidney are particularly rich in vitamin A.
肝脏和肾脏的维生素A含量尤其丰富。