一只弹簧的英语翻译(只是否成PC)

spring
n 3 [C] device of twisted, bent or coiled metal or wire that can be pushed, pulled or pressed but tends to return to its original shape or position when released (used to drive clockwork, make seats more comfortable, etc) 弹簧; 发条: * the springs in an armchair 单座沙发内的弹簧

以上是牛津词典的解释.
[c]表示:可数名词的意思. 所以
a spring就是答案. 说a piece of spring就不对了

a piece of spring