spinor genus

例句：

1. 1. The spiral staircase leads up to the second floor.
   螺旋楼梯通向二楼。
2. 2. The helix of the shell is a natural defense against predators.
   贝壳的螺旋是自然防御捕食者的一种方式。
3. 3. The screwdriver fits into the screw and turns it easily.
   螺丝刀可以很容易地拧入螺丝。