shortage是可数名词吗

　　There is a shortage of fresh water on the island.

　　岛上缺少淡水。

　　Many companies are suffering from a shortage of skilled staff.

　　许多公司苦于缺乏熟练员工。

　　Manufacturing industry was worst affected by the fuel shortage.

　　制造业受燃料短缺的影响最为严重。

　　There is no shortage of things to do in the town.

　　城里不愁找不到活儿干。

　　They face a desperate shortage of clean water.

　　他们面临无污染水源的严重短缺。