standard thimble

例句：

1. 1. The engineer used a standard thimble to tighten the bolts on the machine.
   工程师使用标准套环来紧固机器上的螺栓。
2. 2. The new model of bicycle has a standard thimble that fits all sizes of tires.
   新款自行车的标准套环适合所有尺寸的轮胎。
3. 3.The thimble was made from a material that would not rust and would last for many years.
   套环由一种不会生锈的材料制成，可以持续多年使用。