其第一摆动辊装在第一摆动臂上，第一摆动臂通过带座轴承安装在机 座的前上部分；

A first swing roller is arranged on a first swing arm; the first swing arm is arranged at the front upper part of a stand through a bearing with a seat;

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He was motionless, all but for one finger that moved up and down in front of his face as if he were marking time with it.

他一动也不动，除了一根手指在他的面前上下摆动,好像在用它标记时间。

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