•The cable has a copper wire surrounded by a plastic sheath.电缆是铜丝做的，外面包着塑胶皮。

•The nerves are protected by thin sheaths of fatty tissue.神经由薄薄的脂肪鞘保护着。

•He drew the knife from its jewelled leather sheath.他把刀从镶有珠宝的皮鞘中抽出来。