the free wobble的用法和样例：
例句
- Impulsion may be recognized by the freely swinging back and the participation of all the joints in the forward motion.
自由摆动的背部和身体所有关节都参与向前的运动是动力的表现。 - Until then, physicists had postulated boundary conditions in which no force acted on the ends of the strings, leaving them free to flap around.
当时，物理学家早已假定了没有力作用在弦两端的边界条件，让弦的末端可以自由摆动。
