According to Aristotle, movement in nature is classified into two kinds: natural movement and forcedmovement.
亚里士多德先生说：自然界的运动有两种，一种是天然运动，一种是被迫运动。
2
The monitoring device (20) may particularly be realized by an apparatus that allows the forcedmovement of the joint (1) in synchronization with the generation of X-ray projections.